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<h2>HL Paper 3</h2><div class="specification">
<p><span style="background-color: #ffffff;">Aspartame is formed from the two amino acids aspartic acid (Asp) and phenylalanine (Phe).</span></p>
</div>
<div class="specification">
<p><span style="background-color: #ffffff;">Chromatography is used in the analysis of proteins in the food and pharmaceutical industry.</span></p>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p><span style="background-color: #ffffff;">Draw the structure of the dipeptide Asp–Phe using section 33 of the data booklet.</span></p>
<div class="marks">[2]</div>
<div class="question_part_label">a.</div>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p><span style="background-color: #ffffff;">Describe, using another method, how a mixture of four amino acids, alanine, arginine, glutamic acid and glycine, could be separated when placed in a buffer solution of pH 6.0.</span></p>
<div class="marks">[3]</div>
<div class="question_part_label">b(i).</div>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p><span style="background-color: #ffffff;">Suggest why alanine and glycine separate slightly at pH 6.5.</span></p>
<div class="marks">[1]</div>
<div class="question_part_label">b(ii).</div>
</div>
<div class="question" style="padding-left: 20px; padding-right: 20px;">
<p><span style="background-color: #ffffff;">Calculate the ratio of [A<sup>−</sup>] : [HA] in a buffer of pH 6.0 given that p<em>K</em><sub>a</sub> for the acid is 4.83, using section 1 of the data booklet.</span></p>
<div class="marks">[1]</div>
<div class="question_part_label">b(iii).</div>
</div>
<h2 style="margin-top: 1em">Markscheme</h2>
<div class="question" style="padding-left: 20px;">
<p><img src="data:image/png;base64,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" width="298" height="167"></p>
<p><span style="background-color: #ffffff;">amide link (<em>eg,</em> CONH) ✔</span></p>
<p><span style="background-color: #ffffff;">correct order and structures of amino acids ✔</span></p>
<p><em><span style="background-color: #ffffff;"> NOTE: Accept a skeletal formula or a full or condensed structural formula.<br>Accept zwitterion form of dipeptide.<br>Accept CO–NH but <strong>not</strong> CO–HN for amide link.</span></em></p>
<div class="question_part_label">a.</div>
</div>
<div class="question" style="padding-left: 20px;">
<p><span style="background-color: #ffffff;"><em>Any three of:</em><br>«gel» electrophoresis «technique»<br><em><strong>OR</strong></em><br>mixture «in buffer solution» placed on gel/paper ✔</span></p>
<p><span style="background-color: #ffffff;">voltage/potential «difference» applied ✔</span></p>
<p><span style="background-color: #ffffff;">amino acids move differently «depending on pH/isoelectric point» ✔</span></p>
<p><span style="background-color: #ffffff;">compare/measure distances travelled/<em>R</em><sub>f</sub> values ✔</span></p>
<p><em>NOTE: <span style="background-color: #ffffff;">Accept “mixture placed on plate covered with polyacrylamide «gel» <strong>OR</strong> “mixture put in a gel «medium»”.</span></em></p>
<div class="question_part_label">b(i).</div>
</div>
<div class="question" style="padding-left: 20px;">
<p><span style="background-color: #ffffff;">different sizes/molar masses/chain lengths «so move with different speeds» ✔</span></p>
<p><em>NOTE: <span style="background-color: #ffffff;">Do <strong>not</strong> accept “different side-chains/R-groups/number of carbons”.</span></em></p>
<div class="question_part_label">b(ii).</div>
</div>
<div class="question" style="padding-left: 20px;">
<p><span style="background-color: #ffffff;">«6.0 = 4.83 + log <span class="mjpage"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="\frac{{\left[ {{{\text{A}}^ - }} \right]}}{{\left[ {{\text{HA}}} \right]}}"> <mfrac> <mrow> <mrow> <mo>[</mo> <mrow> <mrow> <msup> <mrow> <mtext>A</mtext> </mrow> <mo>−</mo> </msup> </mrow> </mrow> <mo>]</mo> </mrow> </mrow> <mrow> <mrow> <mo>[</mo> <mrow> <mrow> <mtext>HA</mtext> </mrow> </mrow> <mo>]</mo> </mrow> </mrow> </mfrac> </math></span>»</span></p>
<p><span style="background-color: #ffffff;"><span style="background-color: #ffffff;">«log<span style="display: inline !important;float: none;background-color: #ffffff;color: #000000;font-family: Verdana,Arial,Helvetica,sans-serif;font-size: 14px;font-style: normal;font-variant: normal;font-weight: 400;letter-spacing: normal;text-align: left;text-decoration: none;text-indent: 0px;white-space: normal;"><span class="mjpage"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="\frac{{\left[ {{{\text{A}}^ - }} \right]}}{{\left[ {{\text{HA}}} \right]}}"> <mfrac> <mrow> <mrow> <mo>[</mo> <mrow> <mrow> <msup> <mrow> <mtext>A</mtext> </mrow> <mo>−</mo> </msup> </mrow> </mrow> <mo>]</mo> </mrow> </mrow> <mrow> <mrow> <mo>[</mo> <mrow> <mrow> <mtext>HA</mtext> </mrow> </mrow> <mo>]</mo> </mrow> </mrow> </mfrac> </math></span></span>= 1.17»</span></span></p>
<p><span style="background-color: #ffffff;"><span style="background-color: #ffffff;"><span style="background-color: #ffffff;">«[A<sup>−</sup>] : [HA] =» 14.8 : 1 ✔</span></span></span></p>
<p><em><span style="background-color: #ffffff;"><span style="background-color: #ffffff;"><span style="background-color: #ffffff;"> NOTE: Accept “15:1”.<br>Do <strong>not</strong> accept 1:14.8.</span></span></span></em></p>
<div class="question_part_label">b(iii).</div>
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<h2 style="margin-top: 1em">Examiners report</h2>
<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">a.</div>
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<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">b(i).</div>
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<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">b(ii).</div>
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<div class="question" style="padding-left: 20px;">
[N/A]
<div class="question_part_label">b(iii).</div>
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