File "biological-pigments-answers-1.html"
Path: /ThinkIB/chem/chemistry/page/24870/biological-pigments-answers-1html
File size: 119.37 KB
MIME-type: text/html
Charset: utf-8
<!DOCTYPE html>
<html lang="en">
<head>
<!-- Google Tag Manager -->
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
})(window,document,'script','dataLayer','GTM-K5VSFSN');
</script>
<!-- End Google Tag Manager -->
<meta http-equiv="x-ua-compatible" content="IE=Edge">
<title>DP Chemistry: Biological pigments answers</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="robots" content="index, follow"><meta name="googlebot" content="noarchive">
<!-- Removed by WebCopy --><!--<base href="https://www.thinkib.net">--><!-- Removed by WebCopy --><meta name="keywords" content="chemistry, inthinking, IB, IBDP, IBMYP, thinkib, baccalaureate, education"><meta name="description" content="1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and the colour observed is the transmitted complementary colour. (b) There is greater conjugation in the structure of cyanidin in the alkaline solution (due..."><meta prefix="og: http://ogp.me/ns#" property="og:title" name="og:title" content="DP Chemistry: Biological pigments answers">
<meta prefix="og: http://ogp.me/ns#" property="og:image" content="https://www.thinkib.net/img/teacher-resources.png">
<meta prefix="og: http://ogp.me/ns#" property="og:description" name="og:description" content="1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and the colour observed is the transmitted complementary colour. (b) There is greater conjugation in the structure of cyanidin in the alkaline solution (due...">
<meta prefix="og: http://ogp.me/ns#" property="og:url" name="og:url" content="https://www.thinkib.net/chemistry/page/24870/biological-pigments-answers">
<meta prefix="og: http://ogp.me/ns#" property="og:site_name" name="og:site_name" content="Subscription websites for IB teachers & their classes">
<meta prefix="og: http://ogp.me/ns#" property="og:locale" name="og:locale" content="en">
<meta prefix="og: http://ogp.me/ns#" property="og:type" name="og:type" content="website">
<meta name="description" content="1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and the colour observed is the transmitted complementary colour. (b) There is greater conjugation in the structure of cyanidin in the alkaline solution (due...">
<meta name="image" content="https://www.thinkib.net/img/teacher-resources.png">
<meta name="keywords" content="Chemistry, Inthinking, IB, IBDP, IBMYP, Thinkib, Baccalaureate, Education, inthinking, thinkib, baccalaureate, education, diploma, international baccalaureate, international schools, high school degree, middle years, middle years programme, international education, IB diploma">
<meta itemprop="name" content="DP Chemistry: Biological pigments answers">
<meta itemprop="description" content="1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and the colour observed is the transmitted complementary colour. (b) There is greater conjugation in the structure of cyanidin in the alkaline solution (due...">
<meta itemprop="image" content="https://www.thinkib.net/img/teacher-resources.png">
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:title" content="DP Chemistry: Biological pigments answers">
<meta name="twitter:description" content="1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and the colour observed is the transmitted complementary colour. (b) There is greater conjugation in the structure of cyanidin in the alkaline solution (due...">
<meta name="twitter:image" content="https://www.thinkib.net/img/teacher-resources.png">
<meta name="twitter:creator" content="@InThinker">
<link href="../../../css/bootstrap.min-1.css" rel="stylesheet" media="screen">
<link href="../../../css/font-awesome-4.7.0/css/font-awesome.min-1.css" rel="stylesheet">
<link href="../../../css/top-nav.min-1.css?v=202211301945" rel="stylesheet" media="screen">
<link href="../../../css/style.min-1.css?v=202212191040" rel="stylesheet" media="screen">
<link href="../../../css/style-ib.min-1.css?v=202211282000" rel="stylesheet" media="screen">
<link rel="stylesheet" type="text/css" href="../../../js/jq-fancybox/jquery.fancybox.min-1.css">
<link href="../../../js/jq-fancybox/jquery.fancybox.min-1.css" type="text/css" rel="stylesheet">
<script>function inIframe () {try {return window.self !== window.top;} catch (e) {return true;}}if( inIframe() ) { window.location.href = "/mb/embed?mbtest=1&ref=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"; }</script><link rel="stylesheet" href="../../../assets/css/ckeditor5-custom-1.css" type="text/css"><link rel="stylesheet" href="../../../css/snippets.min-1.css?v=202210181500"><link rel="stylesheet" href="../../../css/article.min-1.css?v=202212151220"><link rel="stylesheet" href="../../../css/toplevel-map-1.css"><link rel="stylesheet" href="../../../css/std-access/std-access-tools.min-2.css?v=202204280950"><link href="../../../css/std-access/std-assignments.min-1.css?v=20220127" rel="stylesheet" media="screen"><link href="../../../js/jq-datepicker/datepicker.min-1.css" type="text/css" rel="stylesheet"><link rel="stylesheet" href="../../../css/side-nav.min-1.css?v=20220520"><script src="../../../js/localdates.min-1.js?v=202009290900"></script><script src="../../../js/ifvisible.min-1.js"></script><script>ifvisible.setIdleDuration(300);</script><script>var tibSitename = "chemistry";</script>
<script>
const SITE_TAG = "ib"
const SITE_WEB = "ThinkIB.net"
const SITE_DOMAIN = "www.thinkib.net"
const SITE_URI = "https://thinkib.net"
const SITE_CLIENT_CODE = "TIB000001"
let imageThinker = "../../../img/header-thinker-ib.svg";
let imageStudent = "img/header-student-thinkib.svg";
</script>
<script>var userHash = "IB Docs (2) Team", userTicket = "IB Docs (2) Team";</script><script src="../../../js/user/local-stats.min-1.js?v=202102101800"></script><link rel="apple-touch-icon-precomposed" sizes="57x57" href="../../../img/favicon/thinkib/apple-touch-icon-57x57-1.png"><link rel="apple-touch-icon-precomposed" sizes="114x114" href="../../../img/favicon/thinkib/apple-touch-icon-114x114-1.png"><link rel="apple-touch-icon-precomposed" sizes="72x72" href="../../../img/favicon/thinkib/apple-touch-icon-72x72-1.png"><link rel="apple-touch-icon-precomposed" sizes="144x144" href="../../../img/favicon/thinkib/apple-touch-icon-144x144-1.png"><link rel="apple-touch-icon-precomposed" sizes="60x60" href="../../../img/favicon/thinkib/apple-touch-icon-60x60-1.png"><link rel="apple-touch-icon-precomposed" sizes="120x120" href="../../../img/favicon/thinkib/apple-touch-icon-120x120-1.png"><link rel="apple-touch-icon-precomposed" sizes="76x76" href="../../../img/favicon/thinkib/apple-touch-icon-76x76-1.png"><link rel="apple-touch-icon-precomposed" sizes="152x152" href="../../../img/favicon/thinkib/apple-touch-icon-152x152-1.png"><link rel="icon" type="image/png" href="../../../img/favicon/thinkib/favicon-196x196-1.png" sizes="196x196"><link rel="icon" type="image/png" href="../../../img/favicon/thinkib/favicon-96x96-1.png" sizes="96x96"><link rel="icon" type="image/png" href="../../../img/favicon/thinkib/favicon-32x32-1.png" sizes="32x32"><link rel="icon" type="image/png" href="../../../img/favicon/thinkib/favicon-16x16-1.png" sizes="16x16"><link rel="icon" type="image/png" href="../../../img/favicon/thinkib/favicon-128-1.png" sizes="128x128"><meta name="application-name" content=" "><meta name="msapplication-TileColor" content="#FFFFFF"><meta name="msapplication-TileImage" content="https://www.thinkib.net/img/favicon/thinkib/mstile-144x144.png"><meta name="msapplication-square70x70logo" content="https://www.thinkib.net/img/favicon/thinkib/mstile-70x70.png"><meta name="msapplication-square150x150logo" content="https://www.thinkib.net/img/favicon/thinkib/mstile-150x150.png"><meta name="msapplication-wide310x150logo" content="https://www.thinkib.net/img/favicon/thinkib/mstile-310x150.png"><meta name="msapplication-square310x310logo" content="https://www.thinkib.net/img/favicon/thinkib/mstile-310x310.png">
</head>
<body onunload="" class="">
<!-- Google Tag Manager (noscript) -->
<noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-K5VSFSN" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<!-- End Google Tag Manager (noscript) -->
<div id="header">
<div class="wmap">
<div class="layout-wrapper">
<div class="container-fluid">
<div class="pull-right visible-phone">
<a href="https://www.inthinking.net">
<img class="header-logo" src="../../../img/header-logo-1.svg" style="height: 45px; width: auto;">
</a>
</div>
<div class="visible-phone" style="clear:both;"></div>
<div class="pull-left">
<h1><a href="/chemistry"><span style="">IBDP Chemistry brought to you by the IB Docs (2) Team</span></a></h1>
<p class="slogan hidden-phone"><span class="slogan"><em>InThinking</em> Subject Sites for teachers & their classes</span></p>
<p class="hidden-phone">Website by <strong>Geoffrey Neuss</strong></p>
<p class="hidden-phone">Updated 2 JIB Docs (2) Teamary 2023</p>
</div>
<div class="visible-phone" style="clear:both;"></div>
<div class="pull-right text-right header-right">
<a class="hidden-phone" href="https://www.inthinking.net">
<img class="header-logo" src="../../../img/header-logo-1.svg" style="height: 70px; width: auto;">
</a>
<div class="search">
<a href="#" class="toggle-menu-search" data-toggle="dropdown">
<i class="fa fa-2x fa-search"></i>
</a>
</div>
</div>
</div>
</div>
</div>
</div>
<div id="topmenu">
<div class="layout-wrapper">
<div>
<nav class="top-nav"><ul class="level-0"><li class=""><a href="../../../chemistry.html"><i class="fa fa-home"></i> Home</a><ul><li class=""><a href="/subscribe"><i class="fa fa-globe fixwidth"></i> Subscribe today</a></li><li class=""><a href="chemistry/sitemap"><i class="fa fa-sitemap fixwidth"></i> Sitemap</a></li><li class=""><a href="chemistry/last-updates"><i class="fa fa-file-text-o fixwidth"></i> Latest updates</a></li><li class=""><a href="chemistry/teaching-materials"><i class="fa fa-puzzle-piece fixwidth"></i> Teaching materials</a></li><li class=""><a href="chemistry/blog"><i class="fa fa-paperclip fixwidth"></i> Blog</a></li><li class=""><a href="chemistry/twitter"><i class="fa fa-twitter fixwidth"></i> Tweets</a></li><li><a><i class="fa fa-external-link fixwidth"></i> <em>InThinking</em> sites</a><ul><li><a class="text-right" href="https://thinkib.net"><span class="pull-left"> All subjects</span> <em style="opacity: .8;">www.thinkib.net</em></a></li><li><a href="https://www.thinkib.net/biology" target="_blank">IBDP Biology</a></li><li><a href="https://www.thinkib.net/businessmanagement" target="_blank">IBDP Business Management</a></li><li><a href="https://www.thinkib.net/economics" target="_blank">IBDP Economics</a></li><li><a href="https://www.thinkib.net/englishalit" target="_blank">IBDP English A Literature</a></li><li><a href="https://www.thinkib.net/englishalanglit" target="_blank">IBDP English A: Language & Literature</a></li><li><a href="https://www.thinkib.net/englishb" target="_blank">IBDP English B</a></li><li><a href="https://www.thinkib.net/ess" target="_blank">IBDP Environmental Systems & Societies</a></li><li><a href="https://www.thinkib.net/frenchb" target="_blank">IBDP French B</a></li><li><a href="https://www.thinkib.net/geography" target="_blank">IBDP Geography</a></li><li><a href="https://www.thinkib.net/german" target="_blank">IBDP German A: Language & Literature</a></li><li><a href="https://www.thinkib.net/history" target="_blank">IBDP History</a></li><li><a href="https://www.thinkib.net/mathanalysis" target="_blank">IBDP Maths: Analysis & Approaches</a></li><li><a href="https://www.thinkib.net/mathapplications" target="_blank">IBDP Maths: Applications & Interpretation</a></li><li><a href="https://www.thinkib.net/physics" target="_blank">IBDP Physics</a></li><li><a href="https://www.thinkib.net/psychology" target="_blank">IBDP Psychology</a></li><li><a href="https://www.thinkib.net/leadership" target="_blank">IB School Leadership</a></li><li><a href="https://www.thinkib.net/spanisha" target="_blank">IBDP Spanish A</a></li><li><a href="https://www.thinkib.net/spanish-abinitio" target="_blank">IBDP Spanish Ab Initio</a></li><li><a href="https://www.thinkib.net/spanishb" target="_blank">IBDP Spanish B</a></li><li><a href="https://www.thinkib.net/teachmaths" target="_blank">teachMathematics</a></li><li><a href="https://www.thinkib.net/visualarts" target="_blank">IBDP Visual Arts</a></li><li><a href="https://www.thinkib.net/myp-englishalanglit" target="_blank">IBMYP English Language & Literature</a></li><li><a href="https://www.thinkib.net/myp-resources" target="_blank">IBMYP Resources</a></li><li><a href="https://www.thinkib.net/myp-spanishb" target="_blank">IBMYP Spanish Language Acquisition</a></li><li><a href="https://www.thinkib.net/ibcp" target="_blank">IB Career-related Programme</a></li><li><a href="https://www.thinkigcse.net" target="_blank"><strong>ThinkIGCSE</strong> - <em>Subject sites for IGCSE teachers</em></a></li></ul></li></ul><li><li><a href="../16256/start-here-1.html">Start here</a><ul class="level-1"><li><a href="../36257/how-to-navigate-the-site-1.html">How to navigate the site</a></li><li><a href="../24826/using-student-access--1.html" class="father">Using student access </a><ul class="level-2"><li><a href="../27330/creating-student-accounts--1.html">Creating student accounts </a></li><li><a href="../32806/short-cut-to-give-students-access-to-a-page-1.html">Short cut to give students access to a page</a></li><li><a href="../27328/setting-assignments-1.html">Setting assignments</a></li><li><a href="../27351/managing-student-accounts-mark-book-1.html">Managing student accounts & mark book</a></li><li><a href="../27362/using-qbank-1.html">Using qBank</a></li></ul></li><li><a href="../16257/for-teachers-new-to-ib-chemistry-1.html" class="father">For teachers new to IB Chemistry</a><ul class="level-2"><li><a href="../16258/dart-board-chemistry-1.html">'Dart board' chemistry</a></li><li><a href="../16274/essential-resources-1.html">Essential resources</a></li><li><a href="../16276/syllabus-1.html">Syllabus</a></li><li><a href="../16278/possible-teaching-schedule-1.html">Possible teaching schedule</a></li></ul></li></ul></li><li><a href="../46318/teaching-learning-resources-1.html">Teaching, learning & resources</a><ul class="level-1"><li><a href="../17394/approaches-to-teaching-1.html" class="father">Approaches to teaching</a><ul class="level-2"><li><a href="../17395/teaching-styles--1.html">Teaching styles </a></li><li><a href="../17396/teaching-skills--1.html">Teaching skills </a></li><li><a href="../17398/workshops--1.html">Workshops </a></li><li><a href="../17397/teacher-recommendations--1.html">Teacher recommendations </a></li></ul></li><li><a href="../27280/approaches-to-learning-1.html" class="father">Approaches to learning</a><ul class="level-2"><li><a href="../27208/thinking-skills-1.html">Thinking skills</a></li><li><a href="../27216/reflection-1.html">Reflection</a></li><li><a href="../27209/communication-skills-1.html">Communication skills</a></li><li><a href="../27211/social-skills-1.html">Social skills</a></li><li><a href="../27232/self-management-1.html">Self-management</a></li><li><a href="../27312/research-1.html">Research</a></li></ul></li><li><a href="../17120/resources-1.html" class="father">Resources</a><ul class="level-2"><li><a href="../17119/ib-specific-books-1.html">IB specific books</a></li><li><a href="../17121/general-text-books-1.html">General text books</a></li><li><a href="../17131/post-ib-text-books-1.html">Post IB text books</a></li><li><a href="../17132/journals-1.html">Journals</a></li><li><a href="../17133/newspaper-articles-1.html">Newspaper articles</a></li><li><a href="../17124/demonstrations-1.html">Demonstrations</a></li><li><a href="../17139/chemistry-videos-1.html">Chemistry videos</a></li><li><a href="../17140/web-links-1.html">Web links</a></li><li><a href="../17138/chemistry-apps-1.html">Chemistry apps</a></li><li><a href="../17348/novel-uses-for-the-ib-data-booklet--1.html">Novel uses for the IB data booklet </a></li><li><a href="../17392/books-for-enjoyment--1.html">Books for enjoyment </a></li></ul></li><li><a href="../27313/unit-plans-1.html">Unit plans</a></li><li><a href="../22523/critical-thinking-1.html">Critical thinking</a></li><li><a href="../18044/do-you-speak-ib-1.html" class="father">Do you speak IB?</a><ul class="level-2"><li><a href="../17382/changes-to-terminology-1.html">Changes to terminology</a></li></ul></li><li><a href="../32761/school-closures-and-distance-learning-1.html">School closures and distance learning</a></li></ul></li><li><a href="../16347/core-ahl-1.html">Core & AHL</a><ul class="level-1"><li><a href="../16344/syllabus-1.html">Syllabus</a></li><li><a href="../16329/teaching-each-topic-sub-topic-1.html" class="father">Teaching each topic & sub-topic</a><ul class="level-2"><li><a href="../16328/topic-1-1.html">Topic 1</a></li><li><a href="../16907/topics-2-12--1.html">Topics 2 & 12 </a></li><li><a href="../17021/topics-3-13-1.html">Topics 3 & 13</a></li><li><a href="../17114/topics-4-14-1.html">Topics 4 & 14</a></li><li><a href="../17669/topics-5-15--1.html">Topics 5 & 15 </a></li><li><a href="../17848/topics-6-16-1.html">Topics 6 & 16</a></li><li><a href="../18038/topics-7-17--1.html">Topics 7 & 17 </a></li><li><a href="../18120/topics-8-18--1.html">Topics 8 & 18 </a></li><li><a href="../18350/topics-9-19-1.html">Topics 9 & 19</a></li><li><a href="../18475/topics-10-20--1.html">Topics 10 & 20 </a></li><li><a href="../17285/topics-11-21--1.html">Topics 11 & 21 </a></li></ul></li><li><a href="../16441/the-nature-of-science-1.html" class="father">The Nature of Science</a><ul class="level-2"><li><a href="../16450/key-terms-concepts-1.html">Key terms & concepts</a></li><li><a href="../34566/nos-critical-thinking-1.html">NOS & Critical Thinking</a></li><li><a href="../32100/how-the-elements-were-named-1.html">How the elements were named</a></li><li><a href="../36753/the-culture-of-chemistry-1.html">The Culture of Chemistry</a></li><li><a href="../17333/nature-of-science-questions-1.html">Nature of Science questions</a></li></ul></li><li><a href="../16413/incorporating-im-tok-utilization-etc-1.html" class="father">Incorporating IM, TOK, 'Utilization' etc.</a><ul class="level-2"><li><a href="../16414/topic-1-1.html">Topic 1</a></li><li><a href="../16916/topics-2-12-1.html">Topics 2 & 12</a></li><li><a href="../17023/topics-3-13--1.html">Topics 3 & 13 </a></li><li><a href="../17055/topics-4-14--1.html">Topics 4 & 14 </a></li><li><a href="../17270/topics-5-15--1.html">Topics 5 & 15 </a></li><li><a href="../17854/topics-6-16--1.html">Topics 6 & 16 </a></li><li><a href="../18041/topics-7-17--1.html">Topics 7 & 17 </a></li><li><a href="../18099/topics-8-18-1.html">Topics 8 & 18</a></li><li><a href="../18349/topics-9-19--1.html">Topics 9 & 19 </a></li><li><a href="../18420/topics-10-20-1.html">Topics 10 & 20</a></li><li><a href="../17269/topics-11-21--1.html">Topics 11 & 21 </a></li></ul></li><li><a href="../17866/utilization-relationships-between-topics--1.html" class="father">'Utilization' - Relationships between topics </a><ul class="level-2"><li><a href="../17867/relating-topics-4-14-to-all-the-other-topics-1.html">Relating Topics 4 & 14 to all the other topics</a></li><li><a href="../17868/example-of-connections-1.html">Example of connections</a></li><li><a href="../34404/hydroxychloroquine-ib-chemistry-1.html">Hydroxychloroquine & IB Chemistry</a></li><li><a href="../35418/ammonium-nitrate-ib-chemistry-1.html">Ammonium nitrate & IB Chemistry</a></li></ul></li><li><a href="../16685/multiple-choice-tests-for-each-topic-1.html" class="father">Multiple choice tests for each topic</a><ul class="level-2"><li><a href="../16687/sl-questions-by-topic-1.html">SL Questions by topic</a></li><li><a href="../16688/hl-questions-by-topic-1.html">HL Questions by topic</a></li></ul></li></ul></li><li class="selected"><a href="../19044/options--1.html">Options </a><ul class="level-1"><li><a href="../19503/option-a--1.html" class="father">Option A </a><ul class="level-2"><li><a href="../19504/introduction-to-materials-science--1.html">Introduction to materials science </a></li><li><a href="../19519/metals-and-icp-spectroscopy-1.html">Metals and ICP spectroscopy</a></li><li><a href="../19541/catalysts--1.html">Catalysts </a></li><li><a href="../19580/liquid-crystals-1.html">Liquid crystals</a></li><li><a href="../19665/polymers--1.html">Polymers </a></li><li><a href="../19672/nanotechnology-1.html">Nanotechnology</a></li><li><a href="../19843/environmental-impact-plastics-1.html">Environmental impact - plastics</a></li><li><a href="../19858/superconducting-metals-x-ray-crystallography--1.html">Superconducting metals & X-ray crystallography </a></li><li><a href="../19666/condensation-polymers-1.html">Condensation polymers</a></li><li><a href="../19916/environmental-impact-heavy-metals-1.html">Environmental impact - heavy metals</a></li></ul></li><li class="selected"><a href="../19284/option-b--1.html" class="father">Option B </a><ul class="level-2"><li><a href="../19290/introduction-to-biochemistry--1.html">Introduction to biochemistry </a></li><li><a href="../19287/proteins-enzymes--1.html">Proteins & enzymes </a></li><li><a href="../19291/lipids-1.html">Lipids</a></li><li><a href="../19299/carbohydrates--1.html">Carbohydrates </a></li><li><a href="../19305/vitamins--1.html">Vitamins </a></li><li><a href="../19313/biochemistry-the-environment--1.html">Biochemistry & the environment </a></li><li><a href="../19336/proteins-enzymes-ahl--1.html">Proteins & enzymes (AHL) </a></li><li><a href="../19347/nucleic-acids--1.html">Nucleic acids </a></li><li class="selected"><a href="../19361/biological-pigments--1.html">Biological pigments </a></li><li><a href="../19366/stereochemistry-in-biomolecules-1.html">Stereochemistry in biomolecules</a></li></ul></li><li><a href="../19390/option-c--1.html" class="father">Option C </a><ul class="level-2"><li><a href="../19391/energy-sources-1.html">Energy sources</a></li><li><a href="../19407/fossil-fuels-1.html">Fossil fuels</a></li><li><a href="../19411/nuclear-fusion-nuclear-fission-reactions-1.html">Nuclear fusion & nuclear fission reactions</a></li><li><a href="../19429/solar-energy-1.html">Solar energy</a></li><li><a href="../19437/environmental-impact-global-warming-1.html">Environmental impact - global warming</a></li><li><a href="../19453/electrochemistry-rechargeable-batteries-fuel-cells-1.html">Electrochemistry, rechargeable batteries & fuel cells</a></li><li><a href="../19458/nuclear-fusion-fission-hl--1.html">Nuclear fusion & fission (HL) </a></li><li><a href="../19470/photovoltaic-cells-and-dsscs-1.html">Photovoltaic cells and DSSCs</a></li></ul></li><li><a href="../19078/option-d-1.html" class="father">Option D</a><ul class="level-2"><li><a href="../19079/pharmaceutical-products-drug-action--1.html">Pharmaceutical products & drug action </a></li><li><a href="../19158/aspirin-penicillin--1.html">Aspirin & penicillin </a></li><li><a href="../19174/opiates-1.html">Opiates</a></li><li><a href="../19184/ph-regulation-of-the-stomach-1.html">pH regulation of the stomach</a></li><li><a href="../19194/antiviral-medications--1.html">Antiviral medications </a></li><li><a href="../19211/environmental-impact-of-some-medications-1.html">Environmental impact of some medications</a></li><li><a href="../19254/taxol-a-chiral-auxiliary-case-study-1.html">Taxol - a chiral auxiliary case study</a></li><li><a href="../19258/nuclear-medicine--1.html">Nuclear medicine </a></li><li><a href="../19273/drug-detection-analysis--1.html">Drug detection & analysis </a></li></ul></li></ul></li><li><a href="../16592/practical-scheme-of-work-ia--1.html">Practical scheme of work & IA </a><ul class="level-1"><li><a href="../16682/internal-assessment-1.html" class="father">Internal Assessment</a><ul class="level-2"><li><a href="../18892/scaffolding-the-investigation-1.html">'Scaffolding' the investigation</a></li><li><a href="../18896/timing-organisation--1.html">Timing & organisation </a></li><li><a href="../18905/choosing-the-research-question-1.html">Choosing the research question</a></li><li><a href="../18946/personal-engagement-1.html">Personal engagement</a></li><li><a href="../18950/exploration-1.html">Exploration</a></li><li><a href="../18957/analysis-1.html">Analysis</a></li><li><a href="../18965/evaluation-1.html">Evaluation</a></li><li><a href="../18966/communication-1.html">Communication</a></li><li><a href="../19882/internal-standardization-of-the-ia-1.html">Internal standardization of the IA</a></li><li><a href="../19901/submitting-the-samples-for-moderation-2.html">Submitting the samples for moderation</a></li><li><a href="../33754/ten-suggestions-for-ias-using-secondary-data-1.html">Ten suggestions for IAs using secondary data</a></li><li><a href="../37544/gaining-full-marks-for-a-databased-ia--1.html">Gaining full marks for a databased IA </a></li><li><a href="../19506/ia-example-marking-exercise--1.html">IA example & marking exercise </a></li><li><a href="../23929/genuine-examples-of-moderated-ia-reports-1.html">Genuine examples of moderated IA reports</a></li><li><a href="../25234/examples-of-teacher-marked-ia-reports--1.html">Examples of teacher-marked IA reports </a></li><li><a href="../37542/history-of-internal-assessment-1.html">History of Internal Assessment</a></li></ul></li><li><a href="../16598/mandatory-laboratory-components-1.html" class="father">Mandatory laboratory components</a><ul class="level-2"><li><a href="../16613/formula-of-magnesium-oxide--1.html">Formula of magnesium oxide </a></li><li><a href="../16612/determining-the-mr-of-an-unknown-gas-1.html">Determining the <i>M</i><sub>r</sub> of an unknown gas</a></li><li><a href="../16615/acid-base-titrations--1.html">Acid-base titrations </a></li><li><a href="../16616/a-green-acid-base-practical-1.html">A green acid-base practical</a></li><li><a href="../16617/analysis-of-aspirin-tablets-1.html">Analysis of aspirin tablets</a></li><li><a href="../16618/caco3-in-egg-shells-1.html">CaCO<sub>3</sub> in egg shells</a></li><li><a href="../16644/enthalpy-changes-1.html">Enthalpy changes</a></li><li><a href="../16631/reaction-rates-1.html">Reaction rates</a></li><li><a href="../16635/rate-dependent-factors-1.html">Rate-dependent factors</a></li><li><a href="../16636/determining-ea-for-a-reaction-1.html">Determining <i>E</i><sub>a</sub> for a reaction</a></li><li><a href="../16637/iodination-of-propanone-1.html">Iodination of propanone</a></li><li><a href="../18144/titrations-with-a-ph-meter-1.html">Titrations with a pH meter</a></li><li><a href="../18355/redox-titration-with-kmno4--1.html">Redox titration with KMnO<sub>4</sub> </a></li><li><a href="../16640/voltaic-cells-1.html">Voltaic cells</a></li><li><a href="../16659/3-d-molecular-modelling--1.html">3-D molecular modelling </a></li></ul></li><li><a href="../17168/other-good-practicals-1.html" class="father">Other good practicals</a><ul class="level-2"><li><a href="../17196/common-chemical-reactions-1.html">Common chemical reactions</a></li><li><a href="../227/elements-oxides-of-the-third-period--1.html">Elements & oxides of the third period </a></li><li><a href="../17239/the-halogens-1.html">The halogens</a></li><li><a href="../17162/boiling-points-of-mixtures-1.html">Boiling points of mixtures</a></li><li><a href="../17170/polarity-of-molecules-1.html">Polarity of molecules</a></li><li><a href="../18083/le-chateliers-principle--1.html">Le Chatelier's principle </a></li><li><a href="../19582/determining-kc-for-an-esterification-reaction-1.html">Determining <i>K</i><sub>c</sub> for an esterification reaction</a></li><li><a href="../18164/redox-reactions-of-vanadium--1.html">Redox reactions of vanadium </a></li><li><a href="../18351/chlorine-in-swimming-pools--1.html">Chlorine in swimming pools </a></li><li><a href="../18178/analysis-of-cuii-ions-in-solution--1.html">Analysis of Cu(II) ions in solution </a></li><li><a href="../18179/percentage-of-copper-in-brass-1.html">Percentage of copper in brass</a></li><li><a href="../18356/electrolytic-cells--1.html">Electrolytic cells </a></li><li><a href="../18598/reactions-of-organic-compounds-1.html">Reactions of organic compounds</a></li><li><a href="../18752/hydrolysis-of-halogenoalkanes-1.html">Hydrolysis of halogenoalkanes</a></li><li><a href="../18784/preparation-of-13-dinitrobenzene--1.html">Preparation of 1,3-dinitrobenzene </a></li><li><a href="../19022/determination-of-an-organic-structure-1.html">Determination of an organic structure</a></li><li><a href="../19887/preparation-of-nylon-66-1.html">Preparation of nylon 6,6</a></li><li><a href="../19343/determination-of-vitamin-c-content--1.html">Determination of vitamin C content </a></li><li><a href="../19342/hydrolysis-of-starch--1.html">Hydrolysis of starch </a></li><li><a href="../19159/preparation-purification-of-aspirin--1.html">Preparation & purification of aspirin </a></li></ul></li><li><a href="../18851/ict-in-practical-work-1.html" class="father">ICT in practical work</a><ul class="level-2"><li><a href="../18852/data-logging--1.html">Data logging </a></li><li><a href="../18853/software-for-graph-plotting--1.html">Software for graph plotting </a></li><li><a href="../18854/spreadsheets-for-data-processing--1.html">Spreadsheets for data processing </a></li><li><a href="../18855/databases-1.html">Databases</a></li><li><a href="../18856/computer-modelling-simulations--1.html">Computer modelling & simulations </a></li></ul></li><li><a href="../16594/group-4-project-1.html" class="father">Group 4 Project</a><ul class="level-2"><li><a href="../16595/practicalities-1.html">Practicalities</a></li><li><a href="../16596/reflective-statement--2.html">Reflective statement </a></li></ul></li><li><a href="../16666/a-new-laboratory-1.html">A new laboratory?</a></li></ul></li><li><a href="../16284/exams-1.html">Exams</a><ul class="level-1"><li><a href="../16286/essential-facts-1.html" class="father">Essential Facts</a><ul class="level-2"><li><a href="../16287/objectives-command-terms-1.html">Objectives & command terms</a></li><li><a href="../16288/grade-descriptors-1.html">Grade descriptors</a></li><li><a href="../16289/grade-boundaries-1.html">Grade boundaries</a></li></ul></li><li><a href="../16302/paper-1-multiple-choice-1.html" class="father">Paper 1 (Multiple Choice)</a><ul class="level-2"><li><a href="../16303/advice-to-students-paper-1-1.html">Advice to students (Paper 1)</a></li><li><a href="../31515/practice-paper-1-exams-1.html">Practice Paper 1 exams</a></li></ul></li><li><a href="../16305/paper-2-1.html" class="father">Paper 2</a><ul class="level-2"><li><a href="../16306/advice-to-students-paper-2-1.html">Advice to students (Paper 2)</a></li><li><a href="../16307/areas-of-difficulty-1.html">Areas of difficulty</a></li></ul></li><li><a href="../16313/paper-3--1.html" class="father">Paper 3 </a><ul class="level-2"><li><a href="../16314/advice-to-students-paper-3-1.html">Advice to students (Paper 3)</a></li><li><a href="../16342/data-response-questions-1.html">Data response questions</a></li><li><a href="../20054/experimental-work-questions-1.html">Experimental work questions</a></li></ul></li><li><a href="../16324/the-examination-process-1.html" class="father">The examination process</a><ul class="level-2"><li><a href="../16316/setting-the-exam-papers-1.html">Setting the exam papers</a></li><li><a href="../16317/predicted-grades-1.html">Predicted grades</a></li><li><a href="../16318/marking-the-papers-1.html">Marking the papers</a></li><li><a href="../16319/commenting-on-the-exams-1.html">Commenting on the exams</a></li><li><a href="../16320/grade-awarding-1.html">Grade Awarding</a></li><li><a href="../16321/enquiry-upon-results-1.html">Enquiry upon results</a></li><li><a href="../16322/chief-examiners-report-1.html">Chief Examiner's report</a></li><li><a href="../16323/retaking-the-exam-1.html">Retaking the exam</a></li></ul></li><li><a href="../16325/faqs-1.html">FAQs</a></li></ul></li><li><a href="../3147/ib-core-1.html">IB Core</a><ul class="level-1"><li><a href="../3149/learner-profile-1.html">Learner Profile</a></li><li><a href="../21735/extended-essays--1.html" class="father">Extended Essays </a><ul class="level-2"><li><a href="../21736/overview--1.html">Overview </a></li><li><a href="../21780/responsibilities-1.html">Responsibilities</a></li><li><a href="../21790/resources-1.html">Resources</a></li><li><a href="../21800/research-1.html">Research</a></li><li><a href="../21804/writing-the-essay-1.html">Writing the essay</a></li><li><a href="../21810/assessment-1.html">Assessment</a></li><li><a href="../22434/summary-of-advice--1.html">Summary of advice </a></li><li><a href="../25272/faqs--1.html">FAQs </a></li></ul></li><li><a href="../307/theory-of-knowledge-tok-1.html" class="father">Theory of Knowledge (TOK)</a><ul class="level-2"><li><a href="../41171/the-12-tok-concepts-1.html">The 12 TOK concepts</a></li><li><a href="../3507/why-tok-chemistry-1.html">Why TOK & Chemistry?</a></li><li><a href="../3505/a-modern-paradigm-1.html">A modern paradigm</a></li></ul></li></ul></li><li><a href="../17783/fast-track-to-tests-questions-1.html">Fast track to tests & questions</a><ul class="level-1"><li><a href="../17784/sl-multiple-choice-tests-on-individual-topics-1.html">SL Multiple choice tests on individual topics</a></li><li><a href="../24351/sl-multiple-choice-quizzes-on-sub-topics-1.html">SL Multiple choice 'quizzes' on sub-topics</a></li><li><a href="../31519/sl-practice-paper-1-exams-1.html">SL Practice Paper 1 exams</a></li><li><a href="../17786/sl-questions-on-each-sub-topic-1.html">SL Questions on each sub-topic</a></li><li><a href="../20431/sl-paper-3-section-a-questions-1.html">SL Paper 3 Section A questions</a></li><li><a href="../17792/sl-questions-on-the-options-1.html">SL Questions on the options</a></li><li><a href="../24897/sl-quizzes-on-option-sub-topics--1.html">SL Quizzes on option sub-topics </a></li><li><a href="../17785/hl-multiple-choice-tests-on-individual-topics-1.html">HL Multiple choice tests on individual topics</a></li><li><a href="../24352/hl-multiple-choice-quizzes-on-sub-topics-1.html">HL Multiple choice 'quizzes' on sub-topics</a></li><li><a href="../31520/hl-practice-paper-1-exams--1.html">HL Practice Paper 1 exams </a></li><li><a href="../17787/hl-questions-on-each-sub-topic--1.html">HL Questions on each sub-topic </a></li><li><a href="../20428/hl-paper-3-section-a-questions-1.html">HL Paper 3 Section A questions</a></li><li><a href="../17793/hl-questions-on-the-options-1.html">HL Questions on the options</a></li><li><a href="../24973/hl-quizzes-on-option-sub-topics-1.html">HL Quizzes on option sub-topics</a></li><li><a href="../41573/printable-versions-of-written-tasks--1.html">Printable versions of written tasks </a></li></ul></li><li><a href="../41465/complete-course-for-students--2.html">Complete course for students </a><ul class="level-1"><li><a href="../27988/full-coverage-of-each-topic-and-sub-topic-2.html" class="father">Full coverage of each topic and sub-topic</a><ul class="level-2"><li><a href="../27959/topic-1-stoichiometric-relationships-1.html">Topic 1 : Stoichiometric relationships</a></li><li><a href="../27960/topics-2-12-atomic-structure-1.html">Topics 2 & 12 : Atomic structure</a></li><li><a href="../27965/topics-3-13-periodicity-1.html">Topics 3 & 13 : Periodicity</a></li><li><a href="../27971/topics-4-14-chemical-bonding-structure-1.html">Topics 4 & 14 : Chemical bonding & structure</a></li><li><a href="../27987/topics-5-15-energeticsthermochemistry-1.html">Topics 5 & 15 : Energetics/thermochemistry</a></li><li><a href="../27995/topics-6-16-chemical-kinetics-1.html">Topics 6 & 16 : Chemical kinetics</a></li><li><a href="../28001/topics-7-17-equilibrium--1.html">Topics 7 & 17 : Equilibrium </a></li><li><a href="../28017/topics-8-18-acids-and-bases--1.html">Topics 8 & 18 : Acids and bases </a></li><li><a href="../28031/topics-9-19-redox-process-1.html">Topics 9 & 19 : Redox process</a></li><li><a href="../28061/topics-10-20-organic-chemistry-1.html">Topics 10 & 20 : Organic chemistry</a></li><li><a href="../28038/topics-11-21-measurement-data-processing-analysis-1.html">Topics 11 & 21 : Measurement, data processing & analysis</a></li><li><a href="../28074/option-a-materials--1.html">Option A : Materials </a></li><li><a href="../28087/option-b-biochemistry-1.html">Option B : Biochemistry</a></li><li><a href="../28098/option-c-energy--1.html">Option C : Energy </a></li><li><a href="../28109/option-d-medicinal-chemistry-1.html">Option D : Medicinal chemistry</a></li></ul></li><li><a href="../41553/practical-work-including-ia-group-4-project--1.html" class="father">Practical work (including IA & Group 4 Project) </a><ul class="level-2"><li><a href="../41528/internal-assessment-1.html">Internal Assessment</a></li><li><a href="../41657/group-4-project-1.html">Group 4 Project</a></li></ul></li><li><a href="../41387/approaches-to-learning--1.html" class="father">Approaches to learning </a><ul class="level-2"><li><a href="../41380/thinking-skills-1.html">Thinking skills</a></li><li><a href="../41383/communication-skills-1.html">Communication skills</a></li><li><a href="../41384/social-skills--1.html">Social skills </a></li><li><a href="../41385/self-management-skills-1.html">Self-management skills</a></li><li><a href="../41386/research-skills-1.html">Research skills</a></li><li><a href="../41382/reflection-skills--1.html">Reflection skills </a></li></ul></li><li><a href="../41488/the-nature-of-science-1.html" class="father">The Nature of Science</a><ul class="level-2"><li><a href="../41489/key-terms-concepts--1.html">Key terms & concepts </a></li><li><a href="../41492/how-the-elements-were-named--1.html">How the elements were named </a></li><li><a href="../41490/nos-critical-thinking-1.html">NOS & Critical Thinking</a></li><li><a href="../41493/the-culture-of-chemistry--1.html">The Culture of Chemistry </a></li><li><a href="../41494/nature-of-science-questions--1.html">Nature of Science questions </a></li></ul></li><li><a href="../41401/external-assessment-exams-1.html" class="father">External assessment (Exams)</a><ul class="level-2"><li><a href="../41403/essential-facts--1.html">Essential Facts </a></li><li><a href="../41409/paper-1-multiple-choice--1.html">Paper 1 (Multiple Choice) </a></li><li><a href="../41417/paper-2--1.html">Paper 2 </a></li><li><a href="../41431/paper-3--1.html">Paper 3 </a></li></ul></li><li><a href="../41662/extended-essay--1.html" class="father">Extended Essay </a><ul class="level-2"><li><a href="../41685/preparation-1.html">Preparation</a></li><li><a href="../41686/researching--1.html">Researching </a></li><li><a href="../42075/writing-the-essay-1.html">Writing the essay</a></li><li><a href="../41687/assessment-1.html">Assessment</a></li></ul></li></ul></li></ul></nav>
</div>
</div>
</div>
<nav id="nav-menu-search" style="display: none;">
<div class="layout-wrapper">
<form class="form-inline" role="search" method="get" action="chemistry/search">
<input id="nav-search" name="s" type="search" placeholder="Search Chemistry..." value="">
<button class="btn btn-sm btn-primary" type="submit">
Search
</button>
<a href="#" class="toggle-menu-search" title="Close">
<i class="fa fa-lg fa-times gray"></i>
</a>
</form>
</div>
</nav>
<div class="layout-wrapper">
<div id="container" class="container-fluid">
<div id="content">
<div class="row-fluid">
<div id="left-column" class="span3"><div class="dropdown" id="userbox"><a class="dropdown-toggle btn" data-toggle="dropdown" onclick="return false;"><img src="../../../img/user/t/IBRR.jpg" style="width: 16px; height: 16px; margin: -2px 0 0 0;"> IB Docs (2) Team <i class="fa fa-caret-down gray"></i></a><ul class="dropdown-menu" style="min-width: 200px"><li><a href="https://www.thinkib.net/chemistry" class="" title=""><i class="fa fa-globe fixwidth colored"></i>IBDP Chemistry</a></li><li class="divider"></li><li><a href="https://www.thinkib.net/chemistry/user" class="" title="Check & modify your profile"><i class="fa fa-user fixwidth colored"></i>My profile</a></li><li><a href="https://www.thinkib.net/chemistry/sitemap" class="" title="Get an overview of the site"><i class="fa fa-sitemap colored fixwidth colored"></i>Sitemap</a></li><li><a href="chemistry/std-access" class="" title="Set up/Manage student access"><i class="fa fa-group fixwidth colored"></i>Student access</a></li><li><a href="https://www.thinkib.net/chemistry/user/teacher-accounts" class="" title="Manage teacher accounts"><i class="fa fa-cogs fixwidth colored"></i>Teacher accounts</a></li><li><a href="https://www.thinkib.net/chemistry/user/bookmarks" class="" title="Manage your bookmarked pages"><i class="fa fa-star fixwidth colored"></i>My favorites</a></li><li><a href="https://www.thinkib.net/chemistry/user/messages" class="" title="Read your messages"><i class="fa fa-envelope-o fixwidth colored"></i>Messages</a></li><li><a href="/help/thinkib" class="pop-up-help" title="Help"><i class="fa fa-info-circle fixwidth colored"></i>Help</a></li><li><a href="https://www.thinkib.net/subscribe/" class="" title="Add / Renew subjects"><i class="fa fa-refresh fixwidth colored"></i>Renew</a></li><li class="divider"></li><li><a href="chemistry?logout=1"><i class="fa fa-power-off fixwidth colored"></i>Log out</a></li></ul></div><div id="std-side-box" class="side-box shadow-md" data-pid="24870">
<div id="std-access-tools" data-pid="24870" data-general-id="3">
<div class="row-fluid accordion-group">
<div class="std-access-tools-header">
<a class="accordion-toggle" data-toggle="collapse" data-parent="#std-access-tools" href="#std-access-tools-content" onclick="return false;">
<i class="fa fa-caret-right white"></i>
Student access tools
</a>
</div>
<div id="std-access-tools-content" class="accordion-body collapse">
<div class="accordion-inner">
<p><i class="fa fa-spin fa-circle-o-notch"></i> Loading...</p>
</div>
</div>
</div>
</div>
</div>
<nav id="sidemenu" class="side-nav"><div class="header"><span style="color: #fff;"><a href="../19044/options--1.html">Options </a></span><span id="sidetreecontrol"><a title="Collapse all" rel="collapse" href="#"><i class="fa fa-minus-circle"></i></a> <a title="Expand all" rel="expand" href="#"><i class="fa fa-plus-circle"></i></a></span></div><ul class="level-0 always-expanded"><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../19503/option-a--1.html" title="Option A ">Option A </a></li><ul class="level-1 "><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19504/introduction-to-materials-science--1.html" title="Introduction to materials science ">Introduction to materials science </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19512/materials-science-introduction-questions--1.html" title="Materials science introduction questions ">Materials science introduction questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26082/mc-test-introduction-to-materials-science-1.html" title="MC test: Introduction to materials science">MC test: Introduction to materials science</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26051/materials-science-introduction-answers--1.html" title="Materials science introduction answers ">Materials science introduction answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19519/metals-and-icp-spectroscopy-1.html" title="Metals and ICP spectroscopy">Metals and ICP spectroscopy</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26109/mc-test-metals-icp-spectroscopy-1.html" title="MC test: Metals & ICP spectroscopy">MC test: Metals & ICP spectroscopy</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19540/metals-icp-spectroscopy-questions-1.html" title="Metals & ICP spectroscopy questions">Metals & ICP spectroscopy questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26052/metals-icp-spectroscopy-answers-1.html" title="Metals & ICP spectroscopy answers">Metals & ICP spectroscopy answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19541/catalysts--1.html" title="Catalysts ">Catalysts </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26518/mc-test-catalysts-1.html" title="MC test: Catalysts">MC test: Catalysts</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19549/catalysts-questions--1.html" title="Catalysts questions ">Catalysts questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26053/catalysts-answers--1.html" title="Catalysts answers ">Catalysts answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19580/liquid-crystals-1.html" title="Liquid crystals">Liquid crystals</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26133/mc-test-liquid-crystals-1.html" title="MC test: Liquid crystals">MC test: Liquid crystals</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19592/liquid-crystals-questions--1.html" title="Liquid crystals questions ">Liquid crystals questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26054/liquid-crystals-answers-1.html" title="Liquid crystals answers">Liquid crystals answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19665/polymers--1.html" title="Polymers ">Polymers </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26130/mc-test-polymers-1.html" title="MC test: Polymers">MC test: Polymers</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19667/polymers-questions--1.html" title="Polymers questions ">Polymers questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26055/polymers-answers--1.html" title="Polymers answers ">Polymers answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19672/nanotechnology-1.html" title="Nanotechnology">Nanotechnology</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26759/mc-test-nanotechnology-1.html" title="MC test: Nanotechnology">MC test: Nanotechnology</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19778/nanotechnology-questions--1.html" title="Nanotechnology questions ">Nanotechnology questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26056/nanotechnology-answers--1.html" title="Nanotechnology answers ">Nanotechnology answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19843/environmental-impact-plastics-1.html" title="Environmental impact - plastics">Environmental impact - plastics</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26857/mc-test-environmental-impact-plastics-1.html" title="MC test: Environmental impact - plastics">MC test: Environmental impact - plastics</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19847/environmental-impact-plastics-questions-1.html" title="Environmental impact - plastics questions">Environmental impact - plastics questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26057/environmental-impact-plastics-answers-1.html" title="Environmental impact - plastics answers">Environmental impact - plastics answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19858/superconducting-metals-x-ray-crystallography--1.html" title="Superconducting metals & X-ray crystallography ">Superconducting metals & X-ray crystallography </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26975/mc-test-superconducting-metals-x-ray-crystallography-1.html" title="MC test: Superconducting metals & X-ray crystallography">MC test: Superconducting metals & X-ray crystallography</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19860/superconducting-metals-x-ray-crystallography-questions--1.html" title="Superconducting metals & X-ray crystallography questions ">Superconducting metals & X-ray crystallography questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26058/superconducting-metals-x-ray-crystallography-answers-1.html" title="Superconducting metals & X-ray crystallography answers">Superconducting metals & X-ray crystallography answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19666/condensation-polymers-1.html" title="Condensation polymers">Condensation polymers</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../27130/mc-test-condensation-polymers-1.html" title="MC test: Condensation polymers">MC test: Condensation polymers</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19910/condensation-polymers-questions--1.html" title="Condensation polymers questions ">Condensation polymers questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26059/condensation-polymers-answers-1.html" title="Condensation polymers answers">Condensation polymers answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19916/environmental-impact-heavy-metals-1.html" title="Environmental impact - heavy metals">Environmental impact - heavy metals</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../27097/mc-test-environmental-impact-heavy-metals-1.html" title="MC test: Environmental impact - heavy metals">MC test: Environmental impact - heavy metals</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19926/environmental-impact-heavy-metals-questions--1.html" title="Environmental impact - heavy metals questions ">Environmental impact - heavy metals questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26060/environmental-impact-heavy-metals-answers-1.html" title="Environmental impact - heavy metals answers">Environmental impact - heavy metals answers</a></li></ul></ul><li class="ancestor parent" style="padding-left: 0px"><i class="expander fa fa-caret-right fa-rotate-90"></i><a href="../19284/option-b--1.html" title="Option B ">Option B </a></li><ul class="level-1 expanded"><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19290/introduction-to-biochemistry--1.html" title="Introduction to biochemistry ">Introduction to biochemistry </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24828/mc-test-introduction-to-biochemistry-1.html" title="MC test: Introduction to biochemistry">MC test: Introduction to biochemistry</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19286/introduction-to-biochemistry-questions--1.html" title="Introduction to biochemistry questions ">Introduction to biochemistry questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24860/introduction-to-biochemistry-answers-1.html" title="Introduction to biochemistry answers">Introduction to biochemistry answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19287/proteins-enzymes--1.html" title="Proteins & enzymes ">Proteins & enzymes </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24830/mc-test-proteins-enzymes-1.html" title="MC test: Proteins & enzymes">MC test: Proteins & enzymes</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19289/proteins-enzymes-questions--1.html" title="Proteins & enzymes questions ">Proteins & enzymes questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24862/proteins-enzymes-answers-1.html" title="Proteins & enzymes answers">Proteins & enzymes answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19291/lipids-1.html" title="Lipids">Lipids</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24834/mc-test-lipids-1.html" title="MC test: Lipids">MC test: Lipids</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19292/lipids-questions--1.html" title="Lipids questions ">Lipids questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24863/lipids-answers-1.html" title="Lipids answers">Lipids answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19299/carbohydrates--1.html" title="Carbohydrates ">Carbohydrates </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24851/mc-test-carbohydrates-1.html" title="MC test: Carbohydrates">MC test: Carbohydrates</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19298/carbohydrate-questions--1.html" title="Carbohydrate questions ">Carbohydrate questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24864/carbohydrate-answers-1.html" title="Carbohydrate answers">Carbohydrate answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19305/vitamins--1.html" title="Vitamins ">Vitamins </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24829/mc-test-vitamins-1.html" title="MC test: Vitamins">MC test: Vitamins</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19410/vitamins-questions--1.html" title="Vitamins questions ">Vitamins questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24865/vitamins-answers-1.html" title="Vitamins answers">Vitamins answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19313/biochemistry-the-environment--1.html" title="Biochemistry & the environment ">Biochemistry & the environment </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24946/mc-test-biochemistry-the-environment-1.html" title="MC test: Biochemistry & the environment">MC test: Biochemistry & the environment</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19335/biochemistry-the-environment-questions-1.html" title="Biochemistry & the environment questions">Biochemistry & the environment questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24866/biochemistry-the-environment-answers-1.html" title="Biochemistry & the environment answers">Biochemistry & the environment answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19336/proteins-enzymes-ahl--1.html" title="Proteins & enzymes (AHL) ">Proteins & enzymes (AHL) </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24962/mc-test-proteins-enzymes-ahl-1.html" title="MC test: Proteins & enzymes (AHL)">MC test: Proteins & enzymes (AHL)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19341/proteins-enzymes-hl-questions--1.html" title="Proteins & enzymes (HL) questions ">Proteins & enzymes (HL) questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24867/proteins-enzymes-hl-answers-1.html" title="Proteins & enzymes (HL) answers">Proteins & enzymes (HL) answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19347/nucleic-acids--1.html" title="Nucleic acids ">Nucleic acids </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24993/mc-test-nucleic-acids-1.html" title="MC test: Nucleic acids">MC test: Nucleic acids</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19360/nucleic-acids-questions--1.html" title="Nucleic acids questions ">Nucleic acids questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24869/nucleic-acids-answers-1.html" title="Nucleic acids answers">Nucleic acids answers</a></li></ul><li class="ancestor parent" style="padding-left: 14px"><i class="expander fa fa-caret-right fa-rotate-90"></i><a href="../19361/biological-pigments--1.html" title="Biological pigments ">Biological pigments </a></li><ul class="level-2 expanded"><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25033/mc-test-biological-pigments-1.html" title="MC test: Biological pigments">MC test: Biological pigments</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19365/biological-pigments-questions--1.html" title="Biological pigments questions ">Biological pigments questions </a></li><li class="current" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="biological-pigments-answers-1.html" title="Biological pigments answers">Biological pigments answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19366/stereochemistry-in-biomolecules-1.html" title="Stereochemistry in biomolecules">Stereochemistry in biomolecules</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25034/mc-test-stereochemistry-in-biomolecules--1.html" title="MC test: Stereochemistry in biomolecules ">MC test: Stereochemistry in biomolecules </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19373/stereochemistry-in-biomolecules-questions-1.html" title="Stereochemistry in biomolecules questions">Stereochemistry in biomolecules questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../24871/stereochemistry-in-biomolecules-answers--1.html" title="Stereochemistry in biomolecules answers ">Stereochemistry in biomolecules answers </a></li></ul></ul><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../19390/option-c--1.html" title="Option C ">Option C </a></li><ul class="level-1 "><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19391/energy-sources-1.html" title="Energy sources">Energy sources</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25112/mc-test-energy-sources-1.html" title="MC test: Energy sources">MC test: Energy sources</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19404/energy-sources-questions--1.html" title="Energy sources questions ">Energy sources questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25025/energy-sources-answers-1.html" title="Energy sources answers">Energy sources answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19407/fossil-fuels-1.html" title="Fossil fuels">Fossil fuels</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25178/mc-test-fossil-fuels-1.html" title="MC test: Fossil fuels">MC test: Fossil fuels</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19312/fossil-fuels-questions--1.html" title="Fossil fuels questions ">Fossil fuels questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25123/fossil-fuels-answers--1.html" title="Fossil fuels answers ">Fossil fuels answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19411/nuclear-fusion-nuclear-fission-reactions-1.html" title="Nuclear fusion & nuclear fission reactions">Nuclear fusion & nuclear fission reactions</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25188/mc-test-nuclear-fusion-nuclear-fission-reactions-1.html" title="MC test: Nuclear fusion & nuclear fission reactions">MC test: Nuclear fusion & nuclear fission reactions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19421/nuclear-fusion-nuclear-fission-questions-1.html" title="Nuclear fusion & nuclear fission questions">Nuclear fusion & nuclear fission questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25180/nuclear-fusion-nuclear-fission-answers-1.html" title="Nuclear fusion & nuclear fission answers">Nuclear fusion & nuclear fission answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19429/solar-energy-1.html" title="Solar energy">Solar energy</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25207/mc-test-solar-energy-1.html" title="MC test: Solar energy">MC test: Solar energy</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19430/solar-energy-questions-1.html" title="Solar energy questions">Solar energy questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25189/solar-energy-answers-1.html" title="Solar energy answers">Solar energy answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19437/environmental-impact-global-warming-1.html" title="Environmental impact - global warming">Environmental impact - global warming</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25236/mc-test-environmental-impact-global-warming-1.html" title="MC test: Environmental impact – global warming">MC test: Environmental impact – global warming</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19450/environmental-impact-global-warming-questions--1.html" title="Environmental impact - global warming questions ">Environmental impact - global warming questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25190/environmental-impact-global-warming-answers-1.html" title="Environmental impact - global warming answers">Environmental impact - global warming answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19453/electrochemistry-rechargeable-batteries-fuel-cells-1.html" title="Electrochemistry, rechargeable batteries & fuel cells">Electrochemistry, rechargeable batteries & fuel cells</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25258/mc-test-electrochemistry-rechargeable-batteries-fuel-cells-1.html" title="MC test: Electrochemistry, rechargeable batteries & fuel cells">MC test: Electrochemistry, rechargeable batteries & fuel cells</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19455/electrochemistry-rechargeable-batteries-fuel-cells-questions-1.html" title="Electrochemistry, rechargeable batteries & fuel cells questions">Electrochemistry, rechargeable batteries & fuel cells questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25204/electrochemistry-rechargeable-batteries-fuel-cells-answers-1.html" title="Electrochemistry, rechargeable batteries & fuel cells answers">Electrochemistry, rechargeable batteries & fuel cells answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19458/nuclear-fusion-fission-hl--1.html" title="Nuclear fusion & fission (HL) ">Nuclear fusion & fission (HL) </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25269/mc-test-nuclear-fusion-nuclear-fission-hl-1.html" title="MC test: Nuclear fusion & nuclear fission (HL)">MC test: Nuclear fusion & nuclear fission (HL)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19468/nuclear-fusion-fission-reactions-hl-questions--1.html" title="Nuclear fusion & fission reactions (HL) questions ">Nuclear fusion & fission reactions (HL) questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25205/nuclear-fusion-fission-reactions-hl-answers-1.html" title="Nuclear fusion & fission reactions (HL) answers">Nuclear fusion & fission reactions (HL) answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19470/photovoltaic-cells-and-dsscs-1.html" title="Photovoltaic cells and DSSCs">Photovoltaic cells and DSSCs</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25302/mc-test-photovoltaic-cells-dsscs-1.html" title="MC test: Photovoltaic cells & DSSCs">MC test: Photovoltaic cells & DSSCs</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19471/photovoltaic-cells-and-dsscs-questions--1.html" title="Photovoltaic cells and DSSCs questions ">Photovoltaic cells and DSSCs questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25206/photovoltaic-cells-and-dsscs-answers-1.html" title="Photovoltaic cells and DSSCs answers">Photovoltaic cells and DSSCs answers</a></li></ul></ul><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../19078/option-d-1.html" title="Option D">Option D</a></li><ul class="level-1 "><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19079/pharmaceutical-products-drug-action--1.html" title="Pharmaceutical products & drug action ">Pharmaceutical products & drug action </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25440/mc-test-pharmaceutical-products-drug-action-1.html" title="MC test: Pharmaceutical products & drug action">MC test: Pharmaceutical products & drug action</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19154/pharmaceutical-products-drug-action-questions--1.html" title="Pharmaceutical products & drug action questions ">Pharmaceutical products & drug action questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25270/pharmaceutical-products-drug-action-answers--1.html" title="Pharmaceutical products & drug action answers ">Pharmaceutical products & drug action answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19158/aspirin-penicillin--1.html" title="Aspirin & penicillin ">Aspirin & penicillin </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25684/mc-test-aspirin-penicillin-1.html" title="MC test: Aspirin & penicillin">MC test: Aspirin & penicillin</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19171/aspirin-penicillin-questions-1.html" title="Aspirin & penicillin questions">Aspirin & penicillin questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25313/aspirin-penicillin-answers--1.html" title="Aspirin & penicillin answers ">Aspirin & penicillin answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19174/opiates-1.html" title="Opiates">Opiates</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25494/mc-test-opiates-1.html" title="MC test: Opiates">MC test: Opiates</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19176/opiates-questions-1.html" title="Opiates questions">Opiates questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25356/opiates-answers--1.html" title="Opiates answers ">Opiates answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19184/ph-regulation-of-the-stomach-1.html" title="pH regulation of the stomach">pH regulation of the stomach</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25683/mc-test-ph-regulation-of-the-stomach-1.html" title="MC test: pH regulation of the stomach">MC test: pH regulation of the stomach</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19185/ph-regulation-of-the-stomach-questions--1.html" title="pH regulation of the stomach questions ">pH regulation of the stomach questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25391/ph-regulation-of-the-stomach-answers-1.html" title="pH regulation of the stomach answers">pH regulation of the stomach answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19194/antiviral-medications--1.html" title="Antiviral medications ">Antiviral medications </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25685/mc-test-antiviral-medications-1.html" title="MC test: Antiviral medications">MC test: Antiviral medications</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19195/antiviral-medications-questions-1.html" title="Antiviral medications questions">Antiviral medications questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25521/antiviral-medications-answers--1.html" title="Antiviral medications answers ">Antiviral medications answers </a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19211/environmental-impact-of-some-medications-1.html" title="Environmental impact of some medications">Environmental impact of some medications</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25686/mc-test-environmental-impact-of-some-medications-1.html" title="MC test: Environmental impact of some medications">MC test: Environmental impact of some medications</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19216/environmental-impact-of-some-medications-questions-1.html" title="Environmental impact of some medications questions">Environmental impact of some medications questions</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25628/environmental-impact-of-some-medications-answers-1.html" title="Environmental impact of some medications answers">Environmental impact of some medications answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19254/taxol-a-chiral-auxiliary-case-study-1.html" title="Taxol - a chiral auxiliary case study">Taxol - a chiral auxiliary case study</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25687/mc-test-taxol-a-chiral-auxiliary-case-study-1.html" title="MC test: Taxol - a chiral auxiliary case study">MC test: Taxol - a chiral auxiliary case study</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19256/taxol-questions--1.html" title="Taxol questions ">Taxol questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25638/taxol-answers-1.html" title="Taxol answers">Taxol answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19258/nuclear-medicine--1.html" title="Nuclear medicine ">Nuclear medicine </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26020/mc-test-nuclear-medicine-1.html" title="MC test: Nuclear medicine">MC test: Nuclear medicine</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19270/nuclear-medicine-questions--1.html" title="Nuclear medicine questions ">Nuclear medicine questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25656/nuclear-medicine-answers-1.html" title="Nuclear medicine answers">Nuclear medicine answers</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../19273/drug-detection-analysis--1.html" title="Drug detection & analysis ">Drug detection & analysis </a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26047/mc-test-drug-detection-analysis-1.html" title="MC test: Drug detection & analysis">MC test: Drug detection & analysis</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19274/drug-detection-analysis-questions--1.html" title="Drug detection & analysis questions ">Drug detection & analysis questions </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../25657/drug-detection-analysis-answers--1.html" title="Drug detection & analysis answers ">Drug detection & analysis answers </a></li></ul></ul></ul></nav></div><!-- /#left-column-->
<div id="main-column" class="span9"><article id="main-article"><a id="exit-fs" title="Exit presentation mode" href="#" onclick="return false;"><i class="fa fa-arrows-alt"></i></a><ul class="page-actions no-print stacked nav nav-list visible-desktop"><li><a class="presentation" href="#" onclick="return false;"><i class="fa fa-desktop"></i><span>Presentation mode</span></a></li><li><a class="print-section-blog" href="#" onclick="return false;"><i class="fa fa-print"></i><span>Print this page</span></a></li><li><a class="page-bookmarker stacked" data-ticket="IB Docs (2) Team" data-pid="24870" href="#" onclick="return false;"><i class="fa fa-star"></i><span>Favourite</span></a><textarea data-ticket="IB Docs (2) Team" data-pid="24870" id="editor" class="favcomms hidden" placeholder="Your personal notes..."></textarea></li><li><a class="personal-notes" href="#" onclick="return false;"><i class="fa fa-file-text"></i><span>Personal notes</span></a></li><li><a class="" data-toggle="modal" href="#modal-feedback" onclick="return false;"><i class="fa fa-envelope-o"></i><span>Feedback</span></a></li><li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" data-target="#" href="#"><i class="fa fa-share-alt"></i><span>Share this page</span></a><ul class="dropdown-menu" role="menu"><li><a class="" target="_blank" title="Share on Twitter" href="https://twitter.com/share?text=%22Biological+pigments+answers%22+-+via+%40InThinker+%23chemistry%0A&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-twitter-square"></i><span>Twitter</span></a></li><li><a class="" target="_blank" title="Share on Facebook" href="https://www.facebook.com/sharer.php?u=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers&t=Biological+pigments+answers"><i class="fa fa-facebook-square"></i><span>Facebook</span></a></li><li><a class="" href="http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-linkedin-square"></i><span>LinkedIn</span></a></li><li><a class="" href="https://plus.google.com/share?url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-google-plus-square"></i><span>Google +</span></a></li><li><a class="" href="mailto:?subject=Biological pigments answers&body=1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy,...%0Ahttps%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-envelope"></i><span>Email</span></a></li></ul></li><li><a class="" href="chemistry/teaching-materials"><i class="fa fa-puzzle-piece colored"></i><span>Teaching materials</span></a></li></ul><div class="page-actions no-print navbar inline hidden-desktop"><div class="navbar-inner"><ul class="nav"><li><a class="presentation" href="#" onclick="return false;"><i class="fa fa-desktop"></i></a></li><li><a class="print-section-blog" href="#" onclick="return false;"><i class="fa fa-print"></i></a></li><li><a class="page-bookmarker" data-ticket="IB Docs (2) Team" data-pid="24870" href="#" onclick="return false;"><i class="fa fa-star"></i></a></li><li><a class="personal-notes" href="#" onclick="return false;"><i class="fa fa-file-text"></i></a></li><li><a class="" data-toggle="modal" href="#modal-feedback" onclick="return false;"><i class="fa fa-envelope-o"></i></a></li><li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" data-target="#" href="#"><i class="fa fa-share-alt"></i></a><ul class="dropdown-menu" role="menu"><li><a class="" target="_blank" title="Share on Twitter" href="https://twitter.com/share?text=%22Biological+pigments+answers%22+-+via+%40InThinker+%23chemistry%0A&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-twitter-square"></i><span>Twitter</span></a></li><li><a class="" target="_blank" title="Share on Facebook" href="https://www.facebook.com/sharer.php?u=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers&t=Biological+pigments+answers"><i class="fa fa-facebook-square"></i><span>Facebook</span></a></li><li><a class="" href="http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-linkedin-square"></i><span>LinkedIn</span></a></li><li><a class="" href="https://plus.google.com/share?url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-google-plus-square"></i><span>Google +</span></a></li><li><a class="" href="mailto:?subject=Biological pigments answers&body=1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy,...%0Ahttps%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-envelope"></i><span>Email</span></a></li></ul></li><li><a class="" href="chemistry/teaching-materials"><i class="fa fa-puzzle-piece colored"></i></a></li></ul></div></div><h1 class="section-title">Biological pigments answers</h1><ul class="breadcrumb"><li><a title="Home" href="https://www.thinkib.net/chemistry"><i class="fa fa-home"></i></a><span class="divider"><i class="fa fa-chevron-right"></i></span></li><li><a title="Go to: Options " href="../19044/options--1.html">Options </a><span class="divider"><i class="fa fa-chevron-right"></i></span></li><li><a title="Go to: Option B " href="../19284/option-b--1.html">Option B </a><span class="divider"><i class="fa fa-chevron-right"></i></span></li><li><a title="Go to: Biological pigments " href="../19361/biological-pigments--1.html">Biological pigments </a><span class="divider"><i class="fa fa-chevron-right"></i></span></li><li><span>Biological pigments answers</span></li></ul><div id="std-sidebox-task-added-msg"></div><div id="modal-feedback" class="modal hide fade text-left" tabindex="-1" role="dialog" aria-labelledby="log-in form" aria-hidden="true">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3>Biological pigments answers: Feedback</h3>
</div>
<div class="modal-body">
<form method="post" id="feedback-form">
<div class="row-fluid">
<div class="span12" style="margin: 12px 0">
<p>
Which of the following best describes your feedback?
</p>
<label class="radio" style="float: left; margin-right: 12px">
<input type="radio" checked="checked" value="useful" name="feedback-type">
Recommend
</label><label class="radio" style="float: left; margin-right: 12px">
<input type="radio" value="error" name="feedback-type">
Report a problem
</label><label class="radio" style="float: left; margin-right: 12px">
<input type="radio" value="improve" name="feedback-type">
Suggest an improvement
</label><label class="radio" style="float: left; margin-right: 12px">
<input type="radio" value="other" name="feedback-type">
Other
</label>
</div>
</div>
<div class="row-fluid">
<label>Comments:</label>
<div class="row-fluid">
<textarea class="span12" name="feedback-comment" placeholder="Your feedback... (optional)"></textarea>
</div>
</div>
<input type="hidden" name="feedback-submited" value="1">
</form>
</div>
<div class="modal-footer">
<button class="btn btn-large" type="button" data-dismiss="modal" aria-hidden="true">
<i class="fa fa-remove"></i>
Cancel
</button>
<button class="btn pull-right" id="submit-feedback" onclick="javascript:$('#feedback-form').submit();return false;">
<i class="fa fa-check"></i>
Submit
</button>
</div>
</div><section id="main-content"><h1><img class="ico" src="../../../img/icons/higher-1.png"> Answers to questions on Biological pigments</h1>
<hr class="hidden">Answers to <a href="../19365/biological-pigments-questions--1.html" title="Options » Option B » Biological pigments » Biological pigments questions ">Biological pigments questions </a>
<hr class="hidden">
<p><strong>1. (a) </strong>In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy, which is usually a non-bonding orbital) and<br>
the colour observed is the transmitted complementary colour.<strong> </strong></p>
<p><strong>(b)</strong> There is greater conjugation in the structure of cyanidin in the alkaline solution (due to the ketone group) so it absorbs visible light energy of lower energy/lower frequency/longer wavelength. This means that it absorbs orange light and transmits the complementary colour of blue, whereas in the acidic solution it absorbs green light (which is higher in energy than orange) and transmits red.</p>
<hr class="hidden">
<p><strong>2. (a) </strong>Porphyrin contains extensive conjugation of double bonds (i.e. alternate double and single bonds ) involving the delocalisation of pi electrons so absorbs visible light as electrons are excited to higher energy levels.</p>
<p><strong>(b)</strong> Chlorophyll absorbs light in both the low (red) and high (blue) regions of the visible spectrum so transmits green light which lies in the middle of the visible spectrum.</p>
<p><strong>(c)</strong> Two of nitrogen atoms can lose hydrogen ions so that they can form ionic bonds with metal ions and also they can use their non-bonding electrons to form coordinate compounds (i.e. act as ligands) with the metal ions.</p>
<hr class="hidden">
<p><strong>3. (a)</strong> The interaction between haemoglobin and gaseous oxygen molecules is an example of cooperative binding. As the oxygen binds it alters the shape of the haemoglobin molecule, which increases its affinity to molecular oxygen. It reaches a maximum when all the active sites are saturated.</p>
<p><strong>(b)</strong> Fetal haemoglobin is structurally different to adult haemoglobin and can bind oxygen more efficiently. This allows oxygen to diffuse from adult blood to fetal blood across the placenta and for the fetal blood to release a greater proportion of oxygen to developing tissues in the foetus even at relatively low partial pressures of oxygen.<strong> (c)</strong> Changing the pH and increasing the temperature can both cause structural changes to the haemoglobin making it less able to bind to oxygen.</p>
<hr class="hidden">
<p><strong>4.</strong> <strong>(a)</strong> <em>R</em><sub>f</sub> is short for retention factor and is equal to the distance travelled by the sample (in this case the amino acid) divided by the distance travelled by the solvent (or eluent).</p>
<p><strong>(b)</strong> Because the <em>R</em><sub>f</sub><sub> </sub>values for all the 22 possible amino acids have not been determined the amino acids cannot be identified unequivocally. However it seems likely that the protein contains four different amino acids (unless two or more or them have identical <em>R</em><sub>f</sub> values). Three of them are likely to be cysteine and isoleucine and either histidine or lysine. It is possible that the mixture does in fact contain both histidine and lysine. The mixture also contains at least one amino acid that is not in the above list. It may also contain another amino acid that is not on the list but that has the same <em>R</em><sub>f</sub> value as one that is on the list.</p>
<p><strong>(c)</strong> The TLC can be run again using a different ratio of components in the eluent. This will alter the polarity of the eluent and produce different <em>R</em><sub>f</sub> values. This will help to determine whether the mixture does only contain four different amino acids and also whether it contains either histidine or lysine or possibly both.</p>
<hr class="hidden"><br>
Download the <a href="/media/ib/chemistry/files/2014-Options/Option-B/A-Biological-pigments.pdf">Answers to Biological pigments questions <img class="ico" src="../../../img/icons/teacher-notes.png"></a></section></article><section id="media-extras"><div class="page-actions no-print navbar inline hidden-desktop"><div class="navbar-inner"><ul class="nav"><li><a class="presentation" href="#" onclick="return false;"><i class="fa fa-desktop"></i></a></li><li><a class="print-section-blog" href="#" onclick="return false;"><i class="fa fa-print"></i></a></li><li><a class="page-bookmarker" data-ticket="IB Docs (2) Team" data-pid="24870" href="#" onclick="return false;"><i class="fa fa-star"></i></a></li><li><a class="personal-notes" href="#" onclick="return false;"><i class="fa fa-file-text"></i></a></li><li><a class="" data-toggle="modal" href="#modal-feedback" onclick="return false;"><i class="fa fa-envelope-o"></i></a></li><li class="dropdown"><a class="dropdown-toggle" data-toggle="dropdown" data-target="#" href="#"><i class="fa fa-share-alt"></i></a><ul class="dropdown-menu" role="menu"><li><a class="" target="_blank" title="Share on Twitter" href="https://twitter.com/share?text=%22Biological+pigments+answers%22+-+via+%40InThinker+%23chemistry%0A&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-twitter-square"></i><span>Twitter</span></a></li><li><a class="" target="_blank" title="Share on Facebook" href="https://www.facebook.com/sharer.php?u=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers&t=Biological+pigments+answers"><i class="fa fa-facebook-square"></i><span>Facebook</span></a></li><li><a class="" href="http://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-linkedin-square"></i><span>LinkedIn</span></a></li><li><a class="" href="https://plus.google.com/share?url=https%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-google-plus-square"></i><span>Google +</span></a></li><li><a class="" href="mailto:?subject=Biological pigments answers&body=1. (a) In both acidic and alkaline solution cyanidin contains extensive conjugation. The delocalised pi electrons absorbs energy in the visible region of the spectrum as they are excited (to an empty orbital of higher energy,...%0Ahttps%3A%2F%2Fwww.thinkib.net%2Fchemistry%2Fpage%2F24870%2Fbiological-pigments-answers"><i class="fa fa-envelope"></i><span>Email</span></a></li></ul></li><li><a class="" href="chemistry/teaching-materials"><i class="fa fa-puzzle-piece colored"></i></a></li></ul></div></div><div style="border-top: solid 1px #eee;border-bottom: solid 1px #eee;padding: 4px 0 4px 0;line-height: 1em;color: #666;font-size: .8em"><small><em>All materials on this website are for the exclusive use of teachers and students at subscribing schools for the period of their subscription. Any unauthorised copying or posting of materials on other websites is an infringement of our copyright and could result in your account being blocked and legal action being taken against you.</em></small></div></section><section id="comments"></section><div id="std-site-share-link" class="modal fade" tabindex="-1" role="dialog">
<div class="modal-dialog" role="document">
<div class="modal-content">
<div class="modal-body" style="padding: 10px; text-align: center;">
<p>Click the 'Copy URL' button to copy link to another learning platform (e.g. Google Classroom.).</p>
<div id="std-link-url" style="font-size: 20px; font-weight: 700;"></div>
<button id="copy-std-link-url" class="btn btn-default" style="margin-top: 20px;" title="Copy URL to clipboard">
<i class="fa fa-link"></i> Copy URL
</button>
</div>
</div>
</div>
</div>
<div id="modal-std-access-tools-add-task" class="modal hide fade">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3><i class="fa fa-file colored"></i> Biological pigments answers</h3>
<label>
Send to:
<span id="modal-std-access-tools-recipients" style="font-weight: normal"></span>
</label>
</div>
<div class="modal-body">
<form id="form-send-page-task">
<div class="row-fluid">
<div class="span6">
<label>Select deadline</label>
<div class="input-prepend">
<span class="add-on" style="padding: 6px; cursor: pointer;"><i class="fa fa-calendar"></i></span>
<input type="text" name="deadline" class="deadline-datepicker" style="padding: 6px; cursor: pointer;">
</div>
</div>
<div class="span6" style="display: none">
<div class="exam-mode-container">
<label>Exam mode</label>
<div class="input-prepend">
<span class="add-on" style="padding: 6px;">
<i class="fa fa-clock-o"></i>
</span>
<input name="minutes" type="number" min="1" max="120" placeholder="minutes" style="padding: 6px;">
</div>
</div>
</div>
</div>
<div class="row-fluid">
<label>Optional instructions</label>
<div class="row-fluid">
<textarea class="span12" name="resource-notes" style="resize: vertical;"></textarea>
</div>
</div>
<div class="row-fluid">
<div class="score-answers-container" style="margin-top: 15px;"></div>
</div>
<input type="hidden" name="ticket" value="IB Docs (2) Team">
<input type="hidden" name="subject-id" value="3">
<input type="hidden" name="resource-title" value="Biological pigments answers">
<input type="hidden" name="resource-type" value="read">
<input type="hidden" name="resource-id" value="24870">
<input type="hidden" name="dynamic-question-ids" id="std-tools-dyn-quiz-ids" value="">
</form>
</div>
<div class="modal-footer">
<button class="btn" data-dismiss="modal">
Cancel
</button>
<div class="pull-right save-actions">
<span class="btn disabled hidden">
<i class="fa fa-spin fa-circle-o-notch"></i>
Processing...
</span>
<a class="save-task-from-tools also-send btn btn-success" disabled="disabled">
<i class="fa fa-check"></i> Send task
</a>
</div>
</div>
</div>
</div><!-- /#main-column -->
</div>
</div><!-- /#content -->
</div>
</div>
<div id="footer">
<div class="wmap">
<div class="layout-wrapper">
<p>
© <script>document.write(new Date().getFullYear())</script> <em>InThinking / IB Documents (2) Team | Version: 31.01.2023</em>
|
<a target="_self" href="/subscribe/about-us">
About us
</a>
|
<a target="_self" href="/subscribe/legal">
Legal
</a>
|
<a target="_self" href="/subscribe/contact">
Contact
</a>
</p>
<p>
<a class="social" target="_blank" href="https://twitter.com/inthinker">
<img src="../../../social/twitter-square-1.svg"> Twitter
</a>
<a class="social" target="_blank" href="https://www.facebook.com/inthinking.net">
<img src="../../../social/facebook-square-1.svg"> Facebook
</a>
<a class="social" target="_blank" href="https://www.linkedin.com/company/9s4we1">
<img src="../../../social/linkedin-square-1.svg"> LinkedIn
</a>
</p>
</div>
</div>
</div>
<input id="tzoffset" type="hidden" value="-36000"><div id="modal-session-expired" class="modal fade" tabindex="-1" role="dialog" data-backdrop="static" data-keyboard="false">
<div class="modal-dialog" role="document">
<div class="modal-content">
<div class="modal-header">
<h3 style="margin-top: 0">Your session has expired</h3>
</div>
<div class="modal-body" style="padding: 10px;">
<p>You will have to reload and log in again.</p>
</div>
<div class="modal-footer">
<a id="session-expired" class="btn btn-danger pull-right" href="#">
<i class="fa fa-refresh"></i> Reload
</a>
</div>
</div>
</div>
</div>
<!-- Loading scripts at the end of the body means faster page loading -->
<script src="../../../js/jquery-1.10.2.min-1.js"></script>
<script src="../../../js/bootstrap.min-1.js"></script>
<script type="text/javascript" src="../../../js/jq-fancybox/jquery.fancybox.pack-1.js"></script>
<script>var pageId = 24870;</script><script src="../../../js/autosize.min-1.js" media="screen"></script><script src="../../../js/user/section-faves.min-1.js?v=202110111730"></script><script type="text/javascript" src="../../../assets/build/app-1.js?v=202204141130"></script><script type="text/javascript" src="../../../assets/js/ckeditor5-utils.min-1.js?v=20211202"></script><script type="text/javascript" src="../../../js/tib-fullscreen/tib-fullscreen.min-1.js?v=202109221648"></script><script src="../../../js/std-access/std-access-tools.min-1.js?v=202204280950"></script><script src="../../../js/jq-datepicker/bootstrap-datepicker.min-1.js"></script><script src="../../../js/std-access/std-access-tools-add-task.min-1.js?v=202204280950"></script><script src="../../../js/std-access/std-assignments-utils.min-1.js?v=202211281800"></script><script src="../../../js/sidemenu/sidemenu.min-1.js?v=202011301145"></script><script src="../../../js/header-circle.min-1.js?v=20220113"></script><script src="../../../js/password-toggler.min-1.js?v=20220929"></script><script type="text/javascript" src="../../../js/cookies.min-1.js"></script>
<script type="text/javascript">
// The cookies alert
if (! readCookie("displayCookieConsent") && ! readCookie("y") ) {
var cookieMSG = "We use cookies. By continuing to use this website you are giving consent to cookies being used.";
setTimeout(function() {
$.ajax({
cache: true,
url: "js/cookiechoices.js",
dataType: "script",
success: function () {
cookieChoices.showCookieConsentBar(cookieMSG, 'close', 'Read more', "chemistry/legal#cookies");
}
});
}, 2000);
}
</script><script>var sAJAX='/pages/activity/user-stats-page.php?t=IB Docs (2) Team&x=16076';var sData='0ebg+I>F/4F[IxZ4hvT)hIn82Oc2UjpCqiT2UM/85V2gIxZ[hNZ6oiL1+iw6UIp1qiQcoO>MUNws2jLc2O][UxbMLNbYoiQChNf[5[/[UxbOqNuc2|w6IicY/4FMUxbeqIn9LIb4qTZ80Ipc/4F[2vwOqt/6/Obc2iZQ2|ncIicY/4F[]4kfnM&[ak==';var loopSecs = 30;var lsKey = '6cea50e17b81b6f6e9bbe81a6caac71a';</script><script src="../../../js/user/user-stats-page.min-1.js?v=202102101800"></script><script>var sessionUpdateSecs = 600;</script><script type="text/javascript" src="../../../js/session-updater-1.js?v=20200831"></script>
<script type="text/javascript">
$(document).ready(function(){
function padLeft(str,max){return str.length<max?padLeft("0"+str,max):str}function padRight(str,max){return str.length<max?padRight(str+"0",max):str}$("body").on("click",'a[href="#"], a.fancybox-nav, a[data-toggle="tab"], a[data-toggle="dropdown"], a[data-toggle="collapse"], a[data-toggle="modal"]',(function(e){e.preventDefault()}));var topmenuOffset=0,topmenuHeight=0;function fixDiv(t,h){$(window).scrollTop()<topmenuOffset||$("#topmenu ul.level-1").is(":visible")?($("#topmenu").css({position:"",width:""}),$("#topmenu").removeClass("fixed-top"),$("body").css({"padding-top":"0"})):($("#topmenu").css({position:"fixed",top:"0",width:$("#topmenu").width()+"px"}),$("#topmenu").addClass("fixed-top"),$("body").css({"padding-top":topmenuHeight+"px"}))}function fixSearchNav(){var searchMenuTop=topmenuOffset+topmenuHeight,searchMenuH=$("#nav-menu-search").is(":visible")?$("#nav-menu-search").outerHeight():0;$(window).scrollTop()>searchMenuTop-topmenuHeight?($("#nav-menu-search").css({position:"fixed",top:topmenuHeight+"px",left:"0",right:"0"}),$("#nav-menu-search").addClass("fixed-top"),$("body").css("padding-top",topmenuHeight+searchMenuH+"px")):($("#nav-menu-search").css({position:""}),$("#nav-menu-search").removeClass("fixed-top"),$("body").css("padding-top","0"))}$("#topmenu").length&&(topmenuOffset=$("#topmenu").offset().top,topmenuHeight=$("#topmenu").outerHeight(),fixDiv(),$(window).scroll((function(){fixDiv(),fixSearchNav()}))),$("a.toggle-menu-search").on("click",(function(e){e.preventDefault(),$("#nav-menu-search").slideToggle("fast",(function(){$(this).find('input[name="s"]').focus()}))}));var menuH=$("#topmenu").height(),itemH=$("#topmenu > nav > ul > li").height();function fancyScrollTo(id){$("html, body").animate({scrollTop:$("#"+id).offset().top-300},300)}function printSectionBlog(){var w=$(window).width()/2,h,windowSettings="height="+($(window).height()-100)+", width="+w+", left=0, top=0, resizable=no, ";windowSettings+="scrollbars=yes, toolbar=no, menubar=no, location=no, ",windowSettings+="directories=no, status=yes";var myWindow=window.open("","Page printer",windowSettings),containerHtml=["<html>","<head>","<title>Page printer</title>",'<link rel="stylesheet" type="text/css" href="'+window.location.origin+'/css/style.min.css?v=202211152130">','<link rel="stylesheet" type="text/css" href="'+window.location.origin+"/css/style"+SITE_TAG+'.min.css?v=202104061357">','<link rel="stylesheet" type="text/css" href="'+window.location.origin+'/css/snippets.min.css?v=202210181500">','<link rel="stylesheet" type="text/css" href="'+window.location.origin+'/css/article.min.css?v=202210181500">',"</head>","<body>",$("section#main-content").html().replace(/<span\sclass="MJX_Assistive_MathML".*?<\/span>/g,""),"</body>","</html>"].join("");containerHtml=containerHtml.replace(/src="files\//gi,'src="'+window.location.origin+"/files/"),myWindow.document.write(containerHtml),myWindow.document.close(),myWindow.focus(),setTimeout((function(){$.when(myWindow.print()).then(myWindow.close())}),1e3)}function PopupPrint(target){window.print()}$("#topmenu > nav > ul > li").each((function(){if(menuH>itemH&&$(this).position().top<1){var i=itemH+1;$(this).find("ul:first").css("margin-top","-"+i+"px")}})),$("#topmenu > nav > ul > li").on("mouseenter mouseleave",(function(e){var submenu=$("ul:first",this),submenuW=submenu.width();$(this).offset().left+submenuW>$(window).width()&&(submenu.css("right","0"),submenu.find("ul").each((function(){if(!$(this).hasClass("fixed")){var l=$(this).width()+submenuW;$(this).css("margin-left","-"+l+"px"),$(this).addClass("fixed")}})))})),$("a.showhider").click((function(e){e.preventDefault();var box="#"+$(this).attr("rel"),show='<i class="fa fa-eye"></i>',hide='<i class="fa fa-eye-slash"></i>';$(box).slideToggle("fast"),$(this).html($(this).html()==show?hide:show),$(this).attr("title","Show"==$(this).attr("title")?"Hide":"Show")})),$("a.scroll-to").click((function(e){e.preventDefault();var n=$("#"+$(this).data("target")).offset().top-70;$("html, body").animate({scrollTop:n},300)})),$("a.print-section-blog").click((function(e){e.preventDefault(),printSectionBlog()})),$(".print-button").click((function(e){var target;e.preventDefault(),PopupPrint("#"+$(this).data("target-id"))})),$(".alert.alert-success").delay(6e3).hide("fast",fixDiv());var fancyParent=1==$("body").find($("#main-article")).length?"#main-article":"body",fancyOptions={loop:!1,openEffect:"elastic",closeEffect:"elastic",nextEffect:"fade",prevEffect:"fade",parent:fancyParent,helpers:{title:{type:"inside"}}};if($("ul.gallery").each((function(){var rel=$(this).find("li:first-child > a:first-child").attr("rel");$('ul.gallery a.fancy[rel="'+rel+'"]').fancybox(fancyOptions)})),$(".carousel.slide").each((function(){var rel="gallery-"+$(this).data("id");$('.carousel.slide a.fancy[rel="'+rel+'"]').fancybox(fancyOptions)})),$("img.pop").parent("a").each((function(){$(this).attr("title",$(this).children("img").attr("alt"))})),$("img.pop").parent("a").fancybox({loop:!1,helpers:{title:{type:"inside"}}}),!are_cookies_enabled()){var msg='<div class="alert alert-error"><i class="fa fa-warning"></i> Your browser does not accept cookies from this site. Please enable cookies to log in.</div><div class="alert alert-info"><i class="fa fa-question-circle"></i> Enabling cookies in <a target="_blank" style="margin: 0; padding: 0;" href="https://support.mozilla.org/en-US/kb/enable-and-disable-cookies-website-preferences">Firefox</a>, <a target="_blank" style="margin: 0; padding: 0;" href="https://support.google.com/accounts/answer/61416?hl=en">Chrome</a>, <a target="_blank" style="margin: 0; padding: 0;" href="http://windows.microsoft.com/en-us/windows-vista/block-or-allow-cookies">Explorer</a></div>';$("#modal-login .modal-header").append(msg)}if($(".panel-expandable > .panel-heading").click((function(e){e.preventDefault();var panel=$(this).closest(".panel-expandable"),expandables=panel.hasClass("panel-has-footer")?".panel-body, .panel-footer":".panel-body";panel.find(".panel-body").is(":visible")?(panel.find(expandables).slideUp("fast"),panel.find(".expander > .fa-minus").removeClass("fa-minus").addClass("fa-plus")):(panel.find(expandables).slideDown("fast"),panel.find(".expander > .fa-plus").removeClass("fa-plus").addClass("fa-minus"))})),$("#modal-find-out-more").css({width:.8*$("#container").width()+"px","margin-left":-.4*$("#container").width()+"px"}),$(".modal-xxl").length){var modalTopPos=Math.round(.07*$(window).height());$(window).width()>1200&&$(".modal-xxl").css({"max-width":$(window).width()>960?"960px":$(window).width()+"px",width:$(window).width()>960?"960px":$(window).width()+"px","margin-left":$(window).width()>960?"-480px":Math.round($(window).width()/2)}),$(".modal-xxl").css("top",modalTopPos+"px"),$(".modal-xxl").on("shown",(function(){var mHeaderH=$(this).find(".modal-header").outerHeight(),mBody=$(this).find(".modal-body"),mBodyH=mBody.outerHeight(),mFooterH=$(this).find(".modal-footer").outerHeight(),bottomOfTheModal=modalTopPos+mHeaderH+mBodyH+mFooterH;if(bottomOfTheModal<$(window).height())mBodyH+=$(window).height()-bottomOfTheModal-60,mBody.css("max-height",mBodyH+"px");else{$(window).scrollTop(0),modalTopPos=10,$(".modal-xxl").css("top",modalTopPos+"px"),bottomOfTheModal=modalTopPos+mHeaderH+mBodyH+mFooterH,availableScroll=bottomOfTheModal-$(window).height()+modalTopPos;var lastPos=-1;$(window).on("scroll",(function(){var s=$(window).scrollTop()>availableScroll?availableScroll:$(window).scrollTop();newPos=modalTopPos-s,newPos!=lastPos&&($(".modal-xxl").css("top",newPos+"px"),lastPos=newPos)}))}}))}function popupHelp(url,title,w,h){var dualScreenLeft=void 0!==window.screenLeft?window.screenLeft:screen.left,dualScreenTop=void 0!==window.screenTop?window.screenTop:screen.top,width,height,left=(window.innerWidth?window.innerWidth:document.documentElement.clientWidth?document.documentElement.clientWidth:screen.width)/2-w/2+dualScreenLeft,top=(window.innerHeight?window.innerHeight:document.documentElement.clientHeight?document.documentElement.clientHeight:screen.height)/2-h/2+dualScreenTop,newWindow=window.open(url,title,"menubar=no,location=no,resizable=0, width="+w+", height="+h+", top="+top+", left="+left);return window.focus&&(newWindow?newWindow.focus():$('<div class="alert alert-warning" style="margin-bottom: 0px;"><p class="help-block">Pop Up blocked. Please allow Pop Ups in your browser settings.</p></div>').insertBefore("body")),newWindow}if($(".open-student-access-help").click((function(e){e.preventDefault();var h=$(window).height()-20,w=$(window).width()<1280?$(window).width():1280;popupHelp(helpURL,"Student Access Help",w,h)})),$(".pop-up-help").click((function(e){e.preventDefault();var url=$(this).attr("href"),title=$(this).data("title"),h=$(window).height()-20,w;popupHelp(url,title,$(window).width()<1280?$(window).width():1280,h)})),$("section.tib-hiddenbox").length){var count=0;$($("section.tib-hiddenbox").get().reverse()).each((function(){var box=$(this),revealButton;$("<a />").attr("class","btn showhider").attr("rel","hiddenBoxContent"+count).attr("style","margin-bottom: 0;").html('<i class="fa fa-eye"></i>').insertBefore(box);var newContainer=$("<div />").attr("class","hidden-content").attr("id","hiddenBoxContent"+count).html(box.html());newContainer.hide(),newContainer.insertBefore(box),box.remove(),count++})),$("a.showhider").on("click",(function(e){var container=$("#"+$(this).attr("rel"));container.is(":hidden")?(container.fadeIn("fast"),$(this).html('<i class="fa fa-eye-slash"></i>')):(container.fadeOut("fast"),$(this).html('<i class="fa fa-eye"></i>'))}))}
function loadComments(){$.get("pages/comment.php",{action:"get-list",ticket:"IB Docs (2) Team",site_with_comments:"1",general_id:"3",sitename:"chemistry",section_id:"24870"},(function(t){"1"==t.success?($("#comments").html(t.html),"undefined"!=typeof CKEDITOR&&initCommentsEditor()):alert("Error (lc1): please contact support")}),"json")}$(document).ready((function(){loadComments()}));let commentEditor={};function initCommentsEditor(){const t=document.querySelector("#comment-content");t&&CKEDITOR.BasicEditor.create(t,{toolbar:{viewportTopOffset:50,items:["bold","italic","link","subscript","superscript"]},link:{decorators:{addLinkNoFollow:{mode:"automatic",callback:function(t){if(null!=t)return["http://","http://www","https://","https://www","ftp:"].some((o=>t.startsWith(o)))},attributes:{target:"_blank",class:"ck-link",rel:"nofollow"}}}}}).then((function(t){commentEditor=t,commentEditor.execute("heading",{value:"paragraph"})})).catch((function(t){console.error(t)}))}function replaceComment(content,commentId){$("#cancel-comment-post").trigger("click"),$("#comm-"+commentId+" > .comment-content div.comment-text").html(content)}function placeComment(html,fatherId){$("#comment-form").hide(),$("#comment-form textarea").val(""),fatherId>0?($("#comments #comm-"+fatherId).append(html),$("#comments").append($("#comment-form"))):$("#comments").append(html).append($("#comment-form")),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content").removeClass("marked"),$("#comment-form").show("fast")}function update_sticky_comments(arrIds,mode){$.post("pages/edit/update-sticky-comments.php?mode="+mode,{ids:arrIds,ticket:$("#comment-ticket").val()},(function(data){1==data.success?("set"==data.mode&&$("#sticky-"+data.id).parents("div.comment").each((function(e){$(this).find("a.pull-right").first().addClass("sticky"),$(this).find("a.pull-right").first().attr("title","Unmark as important")})),"unset"==data.mode&&($("#sticky-"+data.id).removeClass("sticky"),$("#sticky-"+data.id).attr("title","Mark as important"),$("#sticky-"+data.id).closest("div.comment").find("div.comment").each((function(e){$(this).find("a.pull-right").first().removeClass("sticky"),$(this).find("a.pull-right").first().attr("title","Mark as important")})))):alert(data.error)}),"json")}"undefined"!=typeof CKEDITOR&&initCommentsEditor(),$("section#comments").on("click","#edit-comment",(function(e){e.preventDefault();var commentId=$("form#comment-form #comment-mode").val(),commentContent=commentEditor.getData(),ticket=$("#comment-ticket").val(),sectionId=$("#section-id").val();$.post("pages/comment.php",{action:"edit",comment_id:commentId,content:commentContent,ticket:ticket},(function(data){"0"==data.success?alert(data.error):replaceComment(data.text,commentId)}),"json")})),$("section#comments").on("click","a.edit-comment",(function(e){e.preventDefault(),$(".comment .hidden").removeClass("hidden");var commentId=$(this).data("comment-id"),form=$("form#comment-form"),text=$("#comm-"+commentId+" > .comment-content div.comment-text").html();commentEditor.setData(text),$("form#comment-form textarea").val(""),$("form#comment-form textarea").val(text),$("#comm-"+commentId+" > .comment-content > img").addClass("hidden"),$("#comm-"+commentId+" > .comment-content > div.comment-text").addClass("hidden"),$("#comm-"+commentId+" > .comment-footer").addClass("hidden"),$("#comm-"+commentId+" > .comment-content").append(form),$("form#comment-form #submit-comment").hide(),$("form#comment-form #edit-comment").show(),$("form#comment-form #cancel-comment-post").show(),$("form#comment-form #comment-mode").val(commentId),fancyScrollTo("comment-form"),$("form#comment-form textarea").focus()})),$("section#comments").on("click","#submit-comment",(function(e){e.preventDefault();var commentContent=commentEditor.getData(),fatherId=$("#father-comment").val(),ticket=$("#comment-ticket").val(),sectionId=$("#section-id").val();$.post("pages/comment.php",{action:"post",section_id:sectionId,father_id:fatherId,content:commentContent,ticket:ticket},(function(data){if("0"==data.success)alert(data.error);else{commentEditor.setData(""),placeComment(data.html,fatherId),$("form#comment-form #cancel-comment-post").hide();var n=0;$("#n-comments").text().length>0&&(n=parseInt($("#n-comments").text())),$("#n-comments").text(n+1)}}),"json")})),$("section#comments").on("click","a.reply-comment",(function(e){e.preventDefault(),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content").removeClass("marked");var form=$("form#comment-form"),fatherId=$(this).parent().parent(".comment").attr("rel");form.find("#father-comment").val(fatherId),$(this).parent().parent(".comment").find("> .reply-area").append(form),$(this).find(".fa-reply").removeClass("fa-reply").addClass("fa-arrow-down"),$(this).parent().prev(".comment-content").addClass("marked"),$("form#comment-form #cancel-comment-post").show(),fancyScrollTo("comment-form"),$("form#comment-form textarea").focus()})),$("section#comments").on("click","#cancel-comment-post",(function(e){e.preventDefault(),$(".comment .hidden").removeClass("hidden"),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content.marked").removeClass("marked"),commentEditor.setData("");var form=$("form#comment-form");$("section#comments").append(form),$("form#comment-form #father-comment").val("0"),$("form#comment-form textarea").val(""),$("form#comment-form #comment-mode").val("new"),$("#edit-comment").hide(),$(this).hide(),$("#submit-comment").show()})),$("section#comments").on("click","a.delete-comment",(function(e){var commentId=$(this).data("comment-id"),isFather=$("#comm-"+commentId).children(".comment").length>0,ticket=$("#comment-ticket").val(),msg="You are going to delete a comment.\n\nThis action cannot be undone.\n\nAre you sure?";isFather&&(msg="You are going to delete a comment and all its replies.\n\nThis action cannot be undone.\n\nAre you sure?"),confirm(msg)&&$.post("pages/comment.php",{action:"delete",comment_id:commentId,is_father:isFather,ticket:ticket},(function(data){if("0"==data.success)alert(data.error);else{$("#comm-"+commentId+".comment").replaceWith(data.text);var n=0;$("#n-comments").text().length&&(n=parseInt($("#n-comments").text())),$("#n-comments").text(n-parseInt(data.deleted))}}),"json"),e.preventDefault(),e.stopPropagation()})),$("section#comments").on("click","a.pull-right",(function(e){e.preventDefault();var arrayIds=[];$(this).hasClass("sticky")?(arrayIds.push($(this).closest("div.comment").attr("rel")),$(this).closest("div.comment").find("div.comment").each((function(e){arrayIds.push($(this).attr("rel"))})),update_sticky_comments(arrayIds,"unset")):($(this).parents("div.comment").each((function(e){arrayIds.push($(this).attr("rel"))})),update_sticky_comments(arrayIds,"set"))}));$('#tl-tabs a').click(function (e) {e.preventDefault();$(this).tab('show');});$('img.ico[src="/img/icons/comments.png"]').each((function(){var comment=$(this).attr("title");$(this).removeAttr("title"),$(this).wrap('<a class="tib-popover" href="#" data-content="'+comment+'" data-togle="popover" data-placement="top" />')})),$('img.ico[src="img/icons/comments.png"]').each((function(){var comment=$(this).attr("title");$(this).removeAttr("title"),$(this).wrap('<a class="tib-popover" href="#" data-content="'+comment+'" data-togle="popover" data-placement="top" />')})),$(".tib-popover").popover({html:!0,trigger:"hover",delay:{show:300,hide:300},placement:function(context,source){var position=$(source).position();return position.top>200?"top":position.left<515?"right":position.top<200?"bottom":position.left>515?"left":"top"}}).click((function(e){e.preventDefault()}));var carouselTime=6500;$("div.carousel.slide").carousel({interval:carouselTime}),$(".tib-indicators > img").click((function(){var index=$(this).index(),container;$(this).closest(".carousel.slide").carousel(index)}));
$('a.btn.showhider').click(function(e) {
var showHiderId = $( this ).attr('rel');
if ( $('#'+showHiderId).find('iframe').length > 0 ) {
$('#'+showHiderId+' iframe').each(function() {
if ( $(this).attr('src').indexOf('.pdf') > 0 ) {
this.contentWindow.location.reload(true);
}
});
}
});
var hTopmenu = $('#topmenu').height();
var n = 0;
$('nav.top-nav > ul > li').each(function(k, e) {
if (n > 1) {
var diff = hTopmenu-(e.offsetTop+e.offsetHeight);
$(e).find(' > ul ').css('margin-top', '-'+diff+'px');
}
n++;
});
});
</script>
</body>
</html>