OCR A Level Chemistry A (H432) Chemistry B (H433) PAG 5: Synthesis of an organic liquid Exam Questions and Mark Scheme

OCR A Level Chemistry A (H432)
Chemistry B (H433)


PAG 5: Synthesis of an organic liquid


Exam Questions and Mark Scheme

, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
1. Ethanol is oxidised to ethanoic acid using acidified potassium dichromate(IV) solution. The reaction
is heated under reflux using the equipment shown in the diagram below.




What is the reason for heating under reflux?

A. to ensure even heating
B. to prevent any substances escaping
C. to boil the mixture at a higher temperature
D. to allow efficient mixing

Your answer
[1]


2. A chemist compares the rates of hydrolysis of 1-chloropropane and 1-bromopropane in ethanol.

Which reagent in aqueous solution should be used?

A Silver chloride
B Silver nitrate
C Potassium chloride
D Potassium nitrate

Your answer
[1]

, 3. A student wants to remove an acid impurity from an organic liquid.
What should the student do?

A. Add Na2CO3(aq)
B. Reflux the mixture
C. Add Br2
D. Add MgSO4

Your answer
[1]


4. For which purpose is distillation used?
A to allow a liquid to boil without the loss of vapour
B to purify a liquid product
C to remove an involatile impurity
D to allow further reaction without the loss of product


Your answer [1]


5. The reaction below produces a chloroalkane.
R−OH + HCl → R−Cl + H2O

Which row shows the steps to purify the liquid product in the correct order?

Use a separating Remove
A Distil Dry
funnel unreacted HCl

Remove unreacted Use a separating
B Dry Distil
HCι funnel

Remove unreacted Use a separating
C Distil Dry
HCl funnel

Use a separating Remove unreacted
D Distil Dry
funnel HCι


Your answer [1]