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<title>DP Chemistry: Atomic masses change</title>
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<meta name="description" content="It has been known for a long time that the relative atomic mass, Ar, of lead, Pb, changes slightly depending upon the origin of the lead as it is the end product of natural radioactive decay series. If the lead originates from an area rich in 238-U then the end product will be richer in 206-Pb whereas if the area was originally...">
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auxiliary case study</a></li><li><a href="../../page/19258/nuclear-medicine-.html">Nuclear medicine </a></li><li><a href="../../page/19273/drug-detection-analysis-.html">Drug detection & analysis </a></li></ul></li></ul></li><li><a href="../../page/16592/practical-scheme-of-work-ia-.html">Practical scheme of work & IA </a><ul class="level-1"><li><a href="../../page/16682/internal-assessment.html" class="father">Internal Assessment</a><ul class="level-2"><li><a href="../../page/18892/scaffolding-the-investigation.html">'Scaffolding' the investigation</a></li><li><a href="../../page/18896/timing-organisation-.html">Timing & organisation </a></li><li><a href="../../page/18905/choosing-the-research-question.html">Choosing the research question</a></li><li><a href="../../page/18946/personal-engagement.html">Personal engagement</a></li><li><a href="../../page/18950/exploration.html">Exploration</a></li><li><a href="../../page/18957/analysis.html">Analysis</a></li><li><a href="../../page/18965/evaluation.html">Evaluation</a></li><li><a href="../../page/18966/communication.html">Communication</a></li><li><a href="../../page/19882/internal-standardization-of-the-ia.html">Internal standardization of the IA</a></li><li><a href="../../page/19901/submitting-the-samples-for-moderation.html">Submitting the samples for moderation</a></li><li><a href="../../page/33754/ten-suggestions-for-ias-using-secondary-data.html">Ten suggestions for IAs using secondary data</a></li><li><a href="../../page/37544/gaining-full-marks-for-a-databased-ia-.html">Gaining full marks for a databased IA </a></li><li><a href="../../page/19506/ia-example-marking-exercise-.html">IA example & marking exercise </a></li><li><a href="../../page/23929/genuine-examples-of-moderated-ia-reports.html">Genuine examples of moderated IA reports</a></li><li><a href="../../page/25234/examples-of-teacher-marked-ia-reports-.html">Examples of teacher-marked IA reports </a></li><li><a href="../../page/37542/history-of-internal-assessment.html">History of Internal Assessment</a></li></ul></li><li><a href="../../page/16598/mandatory-laboratory-components.html" class="father">Mandatory laboratory components</a><ul class="level-2"><li><a href="../../page/16613/formula-of-magnesium-oxide-.html">Formula of magnesium oxide </a></li><li><a href="../../page/16612/determining-the-mr-of-an-unknown-gas.html">Determining the <i>M</i><sub>r</sub> of an unknown gas</a></li><li><a href="../../page/16615/acid-base-titrations-.html">Acid-base titrations </a></li><li><a href="../../page/16616/a-green-acid-base-practical.html">A green acid-base practical</a></li><li><a href="../../page/16617/analysis-of-aspirin-tablets.html">Analysis of aspirin tablets</a></li><li><a href="../../page/16618/caco3-in-egg-shells.html">CaCO<sub>3</sub> in egg shells</a></li><li><a href="../../page/16644/enthalpy-changes.html">Enthalpy changes</a></li><li><a href="../../page/16631/reaction-rates.html">Reaction rates</a></li><li><a href="../../page/16635/rate-dependent-factors.html">Rate-dependent factors</a></li><li><a href="../../page/16636/determining-ea-for-a-reaction.html">Determining <i>E</i><sub>a</sub> for a reaction</a></li><li><a href="../../page/16637/iodination-of-propanone.html">Iodination of propanone</a></li><li><a href="../../page/18144/titrations-with-a-ph-meter.html">Titrations with a pH meter</a></li><li><a href="../../page/18355/redox-titration-with-kmno4-.html">Redox titration with KMnO<sub>4</sub> </a></li><li><a href="../../page/16640/voltaic-cells.html">Voltaic cells</a></li><li><a href="../../page/16659/3-d-molecular-modelling-.html">3-D molecular modelling </a></li></ul></li><li><a href="../../page/17168/other-good-practicals.html" class="father">Other good practicals</a><ul class="level-2"><li><a href="../../page/17196/common-chemical-reactions.html">Common chemical reactions</a></li><li><a href="../../page/227/elements-oxides-of-the-third-period-.html">Elements & oxides of the third period </a></li><li><a href="../../page/17239/the-halogens.html">The halogens</a></li><li><a href="../../page/17162/boiling-points-of-mixtures.html">Boiling points of mixtures</a></li><li><a href="../../page/17170/polarity-of-molecules.html">Polarity of molecules</a></li><li><a href="../../page/18083/le-chateliers-principle-.html">Le Chatelier's principle </a></li><li><a href="../../page/19582/determining-kc-for-an-esterification-reaction.html">Determining <i>K</i><sub>c</sub> for an esterification reaction</a></li><li><a href="../../page/18164/redox-reactions-of-vanadium-.html">Redox reactions of vanadium </a></li><li><a href="../../page/18351/chlorine-in-swimming-pools-.html">Chlorine in swimming pools </a></li><li><a href="../../page/18178/analysis-of-cuii-ions-in-solution-.html">Analysis of Cu(II) ions in solution </a></li><li><a href="../../page/18179/percentage-of-copper-in-brass.html">Percentage of copper in brass</a></li><li><a href="../../page/18356/electrolytic-cells-.html">Electrolytic cells </a></li><li><a href="../../page/18598/reactions-of-organic-compounds.html">Reactions of organic compounds</a></li><li><a href="../../page/18752/hydrolysis-of-halogenoalkanes.html">Hydrolysis of halogenoalkanes</a></li><li><a href="../../page/18784/preparation-of-13-dinitrobenzene-.html">Preparation of 1,3-dinitrobenzene </a></li><li><a href="../../page/19022/determination-of-an-organic-structure.html">Determination of an organic structure</a></li><li><a href="../../page/19887/preparation-of-nylon-66.html">Preparation of nylon 6,6</a></li><li><a href="../../page/19343/determination-of-vitamin-c-content-.html">Determination of vitamin C content </a></li><li><a href="../../page/19342/hydrolysis-of-starch-.html">Hydrolysis of starch </a></li><li><a href="../../page/19159/preparation-purification-of-aspirin-.html">Preparation & purification of aspirin </a></li></ul></li><li><a href="../../page/18851/ict-in-practical-work.html" class="father">ICT in practical work</a><ul class="level-2"><li><a href="../../page/18852/data-logging-.html">Data logging </a></li><li><a href="../../page/18853/software-for-graph-plotting-.html">Software for graph plotting </a></li><li><a href="../../page/18854/spreadsheets-for-data-processing-.html">Spreadsheets for data processing </a></li><li><a href="../../page/18855/databases.html">Databases</a></li><li><a href="../../page/18856/computer-modelling-simulations-.html">Computer modelling & simulations </a></li></ul></li><li><a href="../../page/16594/group-4-project.html" class="father">Group 4 Project</a><ul class="level-2"><li><a href="../../page/16595/practicalities.html">Practicalities</a></li><li><a href="../../page/16596/reflective-statement-.html">Reflective statement </a></li></ul></li><li><a 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</a></li><li><a href="../../page/17787/hl-questions-on-each-sub-topic-.html">HL Questions on each sub-topic </a></li><li><a href="../../page/20428/hl-paper-3-section-a-questions.html">HL Paper 3 Section A questions</a></li><li><a href="../../page/17793/hl-questions-on-the-options.html">HL Questions on the options</a></li><li><a href="../../page/24973/hl-quizzes-on-option-sub-topics.html">HL Quizzes on option sub-topics</a></li><li><a href="../../page/41573/printable-versions-of-written-tasks-.html">Printable versions of written tasks </a></li></ul></li><li><a href="../../page/41465/complete-course-for-students-.html">Complete course for students </a><ul class="level-1"><li><a href="../../page/27988/full-coverage-of-each-topic-and-sub-topic.html" class="father">Full coverage of each topic and sub-topic</a><ul class="level-2"><li><a href="../../page/27959/topic-1-stoichiometric-relationships.html">Topic 1 : Stoichiometric relationships</a></li><li><a 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<h1 class="section-title">Atomic masses change</h1>
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<div style="padding: 0 30px;"><p>It has been known for a long time that the relative atomic mass, <em>A</em><sub>r</sub>, of lead, Pb, changes slightly depending upon the origin of the lead as it is the end product of natural radioactive decay series. If the lead originates from an area rich in 238-U then the end product will be richer in 206-Pb whereas if the area was originally rich in 232-Th then the resulting lead will have a slightly higher relative atomic mass as the end product of the decay of 232-Th is 208-Pb. However, the working assumption has always been that the relative atomic masses of the other elements are fixed and precise values are given in all Periodic Tables. This has now changed. Now the only fixed values are for those elements with only one stable isotope such as fluorine, aluminum, sodium and gold.</p><p><img alt="" class="left" height="143" src="../../../ib/chemistry/images/sulfur.jpg" title="Sulfur used to have a relative atomic mass of 32.065. Now its value lies between 32.059 and 32.076." width="160">In a <a href="https://www.degruyter.com/view/journals/pac/83/2/article-p359.xml">recent publication</a> by Michael E. Wieser and Tyler B. Coplen (who work at the University of Calgary,Canada and the U.S. Geological Survey, Reston, USA respectively), the values for the relative atomic masses of eleven common elements have been revised. These are hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine, germanium and thallium. For germanium the change is straightforward – from 72.63 to 72.64. The change is anything but straightforward for the other ten elements. Instead of a single value the relative atomic masses for these ten elements are now given as a range depending upon the precise isotopic make up of the particular source of the sample i.e. its physical, chemical and nuclear history. This will not affect IB chemistry calculations to any great degree as the range is quite small and in fact to two decimal places it often has the same value as that given in the IB Periodic Table (Table 5 of the IB Data Booklet). For example, the range for hydrogen is 1.007 84 to 1.008 11. The old value was 1.007 95 which is actually unchanged at 1.01 when quoted to two decimal places. For some of the other elements the change is just significant to register at two decimal places. Thus boron now will be quoted in the range 10.806 to10.821. So the relative atomic mass to two decimal places could be 10.81 or 10.82 (the old value was 10.811 which corresponds to the value of 10.81 given to two decimal places in the current IB Chemistry Data Booklet).</p><p>In a news report about the published article the International Union of Pure and Applied Chemistry, IUPAC, explains that advances in modern analytical techniques (Option A) means that relative atomic masses can now be measured much more precisely. These small changes, due to the relative abundances of particular stable isotopes in the sample, are important in research and industry. For the IB they can also be related to particular options. For example precise measurements of isotopic carbon abundance and be used to determine purity in food products (Option F) and precise measurements of the nitrogen content can be used for tracing pollutants in streams or underground water systems (Option E). There are uses for Option B: Human biochemistry too. Performance enhancing steroids can be detected in the human body because the relative atomic mass of carbon in natural testosterone is higher than in testosterone from pharmaceutical sources.</p><p>This is an interesting TOK aspect to Chemistry in that it shows how scientific ‘knowledge’ is constantly changing and indeed that the Law of Constant Composition is not as immutable as it was once thought to be (see the <a href="../../page/16414/topic-1.html">page on Topic 1</a> under Including International-mindedness, TOK, and 'Utilization' in Stoichiometric relationships). One other noteworthy aside is that if you look at the articles nowhere is relative atomic mass mentioned. IUAPC still calls it relative atomic weight!</p></div>
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<p class="search-tags"><strong>Tags: </strong><a href="../../search/Law%20of%20Constant%20composition.html">Law of Constant composition</a>, <a href="../../search/%20Data%20Booklet.html"> Data Booklet</a>, <a href="../../search/%20Table%205.html"> Table 5</a>, <a href="../../search/%20Option%20B.html"> Option B</a>, <a href="../../search/%20Option%20A.html"> Option A</a>, <a href="../../search/%20Option%20F.html"> Option F</a>, <a href="../../search/%20Option%20E.html"> Option E</a>, <a href="../../search/%20testosterone.html"> testosterone</a>, <a href="../../search/%20relative%20atomic%20mass.html"> relative atomic mass</a>, <a href="../../search/%20TOK.html"> TOK</a></p>
<div class="prevnext-posts"><div class="pull-right text-right"><a href="../8368/syllabus-content.html" style="font-style: normal">Syllabus content <i class="fa fa-chevron-circle-right"></i></a><br><em class="gray"><small>24 Jan 2011</small></em></div><div class="pull-left"><a href="../8058/practical-work-and-assessment.html" style="font-style: normal"><i class="fa fa-chevron-circle-left"></i> Practical work and assessment</a><br><em class="gray"><small>27 Dec 2010</small></em></div></div>
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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>'))}))}
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"))}));
$('.page-bookmarker').click(function(e){
e.preventDefault();
var pid = $(this).data('pid');
var random = $(this).data('ticket');
bookmarkPage(pid, random);
});
function bookmarkPage(pageId, random){
$.get(
'pages/bookmarks.php',
{
'id' : pageId,
'ticket' : random
},
function(data){
if(data['success'] == '1') {
var buttonTitle = 'Favourite';
if( $('.page-bookmarker').attr('title') == 'Favourite' ) {
buttonTitle = 'Unfavourite';
}
$('.page-bookmarker > i').toggleClass('colored');
$('.page-bookmarker.stacked > span').text(buttonTitle);
$('.page-bookmarker').attr('title', buttonTitle);
}
},
'json'
);
}
// the comment icon becomes a popover
$('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 : true,
trigger : 'hover',
delay : {show: 300, hide: 300},
placement : function (context, source) {
var position = $(source).position();
if (position.top > 200) { return "top";}
if (position.left < 515) { return "right"; }
if (position.top < 200) { return "bottom";}
if (position.left > 515) { return "left"; }
return "top";
}
}).click(function(e){
e.preventDefault();
});
// LIVE CAROUSEL MANAGEMENT
// Miliseconds for the next slide
var carouselTime = 6500;
// Start carousels
$('div.carousel.slide').carousel({interval: carouselTime});
$('.tib-indicators > img').click(function(){
// IN
var index = $(this).index();
var container = $(this).closest('.carousel.slide');
container.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>