Edexcel Jan 2017 (IAL) Paper 1 Q21 (with explained solutions) |

Skip to content

Edexcel Jan 2017 (IAL) Paper 1 Q21

Answers available below

SECTION B Answer ALL the questions. Write your answers in the spaces provided. 21 This question is about cyclohexene which can be used to show the reactions of the alkenes. D O N O T W R I T E I Cyclohexene Data: Boiling temperature = 83(cid:113)C Density = 0.81 g cm3 (a) (i) 1 cm3 of bromine water is shaken with 2 cm3 of cyclohexene in a test tube and the mixture allowed to stand. Describe what you would see before and after shaking. N T H I S A R E A (3)(ii) Draw the skeletal formula of the major organic product of this reaction. (1) 10 *P48367A01024* D O N O T W R I T E I N T H I S A R E A D O N O T W R I T E I N T H I S A R E A<br />
(b) Draw the skeletal formula and give the name of the organic product formed when cyclohexene reacts with potassium manganate(VII) mixed with dilute sulfuric acid. Skeletal formula Name(c) Suggest the skeletal formula of the polymer that would be formed if cyclohexene polymerised. Show two repeat units. (2) (2) (Total for Question 21 = 8 marks) A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D *P48367A01124* 11 Turn over<br />

Show answer

Acceptable Answers Question Number 21(a)(i) (Before shaking) yellow/brown solution (and colourless liquid) ALLOW red-brown/orange (1) (After shaking the aqueous layer) turns colourless OR Decolourises ALLOW Bromine colour fades/disappears (1) Two layers form OR Mention of a layer (1) IGNORE Incorrect name of product in this part Section B Mark Reject Red turns clear/transparent OR solid forms /bubbles/fizzing/ effervescence<br />
Acceptable Answers Question Number 21(a)(ii) Reject Mark The OH and Br must be on two adjacent carbon atoms in either order on a six membered ring IGNORE Point of attachment of OH. Attempt to show stereochemistry eg bonds at odd angles<br />
Question Number 21(b) Acceptable Answers Reject Mark (1) Comment IGNORE Point of attachment of OH; even if H-O Attempt to show stereochemistry Name Cyclohexan(e)-1,2-diol /1,2-dihydroxycyclohexane /1,2-diolcyclohexane IGNORE punctuation (1) Mark name and formula independently ALLOW TE for hexan(e)-n,(n+1)-diol with corresponding formula max1 Otherwise NO TE from incorrect formula<br />
Question Number 21(c) Acceptable Answers First mark Reject Mark Correct structure ALLOW Separated joining bond provided it points to both carbons IGNORE curious bond angles (1) Second mark Extension bonds ALLOW Two cyclic monomers, neither of which may be correct, joined together can score 1 max for extension bonds on adjacent carbons Fused rings with extension bonds on the adjacent carbons can score 1 max Separated extension bonds, where there is a gap between the bond and a cyclic structure are allowed if they are pointing to the carbons adjacent to the joining bond Second mark for any 12 carbon structures (which may be linear) with extension bonds IGNORE Brackets and numbers or letters after brackets eg n, 2, n/2 More than two units (1) (TOTAL FOR QUESTION 21 = 8 MARKS)<br />

Question 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

About us | Need Help? | Feedback

Proudly powered by WordPress | Theme: Sydney by aThemes.