OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
This resource includes exam questions from both Chemistry A and Chemistry B. It is not designed as a
topic test but is instead intended as a document to support the teaching and learning of Module 1 –
Development of practical skills in chemistry.
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
[1]
Your answer
Created in ExamBuilder 1 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
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]
Created in ExamBuilder 2 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
6. 1-Bromobutane is an organic liquid with a boiling point of 102 °C.
A student prepares 1-bromobutane by reacting butan-1-ol with sulfuric acid and sodium bromide.
The student boils the mixture for one hour.
The equation is shown below.
CH3CH2CH2CH2OH + H+ + Br− → CH3CH2CH2CH2Br + H2O
The student obtains a reaction mixture containing an organic layer (density = 1.27 g cm−3) and an
aqueous layer (density = 1.00 g cm−3).
i. * Draw a labelled diagram to show how you would safely set up apparatus for the
preparation. Outline a method to obtain a pure sample of 1-bromobutane from the reaction
mixture.
[6]
Created in ExamBuilder 3 © OCR 2020
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
This resource includes exam questions from both Chemistry A and Chemistry B. It is not designed as a
topic test but is instead intended as a document to support the teaching and learning of Module 1 –
Development of practical skills in chemistry.
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
[1]
Your answer
Created in ExamBuilder 1 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
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]
Created in ExamBuilder 2 © OCR 2020
, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 5: Synthesis of an organic liquid
Practice Exam Questions and Mark Scheme
6. 1-Bromobutane is an organic liquid with a boiling point of 102 °C.
A student prepares 1-bromobutane by reacting butan-1-ol with sulfuric acid and sodium bromide.
The student boils the mixture for one hour.
The equation is shown below.
CH3CH2CH2CH2OH + H+ + Br− → CH3CH2CH2CH2Br + H2O
The student obtains a reaction mixture containing an organic layer (density = 1.27 g cm−3) and an
aqueous layer (density = 1.00 g cm−3).
i. * Draw a labelled diagram to show how you would safely set up apparatus for the
preparation. Outline a method to obtain a pure sample of 1-bromobutane from the reaction
mixture.
[6]
Created in ExamBuilder 3 © OCR 2020
