Edexcel Jun 2012 Paper 4 Q17 (with explained solutions) |

Skip to content

Edexcel Jun 2012 Paper 4 Q17

Answers available below

17 The ester CH3CH2COOCH3 can be formed from the reaction between propanoic acid and methanol with an acid catalyst. CH3CH2COOH + CH3OH U CH3CH2COOCH3 + H2O (a) (i) Name the ester. (1)(ii) The same product can be made using propanoyl chloride instead of propanoic acid. Suggest an additional hazard that could occur using this reagent and GHVFULEHKRZRXZRXOGPLQLPLVHWKLVULVN (2)*P39308A01924* 19 Turn over<br />
(b) Complete the table below to show the amounts of each substance present at equilibrium. Use your values to calculate the equilibrium constant, Kc, for the reaction. CH3CH2COOH CH3OH CH3CH2COOCH3 Initial amounts / mol Equilibrium amounts / mol (3) H2O (Total for Question 17 = 6 marks) TOTAL FOR SECTION B = 52 MARKS 20 *P39308A02024*<br />

Show answer

Correct Answer Methyl propanoate ALLOW methy or methly for methyl Acceptable Answers Question Number 17(a)(ii) Toxic (steamy/misty) fumes/ toxic HCl(gas)/corrosive HCl(gas)/toxic propanoyl chloride/lachrymatory propanoyl chloride (1) So use in a fume cupboard (1) OR Corrosive Propanoyl chloride is (1) So wear gloves when handling (1) Mark Mark Reject Reject HCl(aq)/ hydrochloric acid Just harmful/irritant Just harmful/irritant Reject Mark Question Number 17 (a)(i) Question Number 17(b) Acceptable Answers Table 0.31, 0.16, 1.41 all 3 scores 2, 2 out of 3 scores 1, 1 or 0 out of 3 scores 0 (2) Kc = (0.21/V) x (1.41/V) (0.16/V) x (0.31/V) Kc = 5.969758 Kc = 5.97 (1) IGNORE sf except 1 IGNORE any units ALLOW TE from incorrect values in table. TOTAL FOR SECTION B = 52 MARKS<br />

Question 14 15 16 17 18

About us | Need Help? | Feedback

Proudly powered by WordPress | Theme: Sydney by aThemes.