Edexcel Jan 2012 Paper 5 Q23

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23 (cid:51)(cid:85)(cid:82)(cid:87)(cid:72)(cid:76)(cid:81)(cid:86)(cid:3)(cid:68)(cid:85)(cid:72)(cid:3)(cid:83)(cid:82)(cid:79)(cid:92)(cid:80)(cid:72)(cid:85)(cid:86)(cid:3)(cid:82)(cid:73)(cid:3)(cid:302)(cid:16)(cid:68)(cid:80)(cid:76)(cid:81)(cid:82)(cid:3)(cid:68)(cid:70)(cid:76)(cid:71)(cid:86)(cid:15)(cid:3)(cid:87)(cid:75)(cid:72)(cid:3)(cid:86)(cid:76)(cid:80)(cid:83)(cid:79)(cid:72)(cid:86)(cid:87)(cid:3)(cid:82)(cid:73)(cid:3)(cid:90)(cid:75)(cid:76)(cid:70)(cid:75)(cid:3)(cid:76)(cid:86)(cid:3)(cid:74)(cid:79)(cid:92)(cid:70)(cid:76)(cid:81)(cid:72)(cid:17) NH2 H H HOOC (a) (i) Draw the structural formula for the zwitterion of glycine in the solid state. (ii) Explain, on the basis of your answer to (a)(i), why glycine has a relatively high melting temperature for such a small molecule. PMT (1) (2)(iii) Draw the structure of the protein chain that would be formed if glycine alone were to be polymerized. Show part of the chain containing two glycine residues. (2) 18 *P35302A01828*<br /> PMT *(b) A solution of hydrolysed protein contains the individual amino acids that make up the protein. Briefly state how you would use chromatography, together with known samples of amino acids, to show which amino acids the protein contained. Do not give detailed experimental instructions. (5)(Total for Question 23 = 10 marks) TOTAL FOR SECTION B = 50 MARKS *P35302A01928* 19 Turn over<br />

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