Alcohols (Cambridge (CIE) O Level Chemistry): Exam Questions

Exam code: 5070

3 hours16 questions
1a
1 mark

A student found a recipe for making elderberry wine by fermentation.

  • 1kg elderberries

  • 0.5kg sugar

  • 10g yeast granules

  • 3dm3 water

The student decided to make some elderberry wine using the apparatus below.

fermenting-mixture

The student carried out the following method.

Step 1 The elderberries were crushed.

Step 2 The crushed elderberries and sugar were added to the water and the mixture was boiled for ten minutes. The crushed elderberries were then separated from the mixture.

Step 3 Yeast was added to the liquid when it had cooled to room temperature.

Suggest the purpose of the airlock in the apparatus.

1b
1 mark

What apparatus could be used in Step 1?

1c
2 marks

Draw a labelled diagram of the apparatus used to separate the crushed elderberries from the mixture in Step 2.

1d
1 mark

Why was the yeast in Step 3 not added until the liquid was at room temperature?

1e
3 marks

i)

State one observation during the fermentation.

 

[1]

 

ii)

Suggest how the rate of the fermentation reaction could be measured.

 

[2]

1f
1 mark

Name the method that could be used to separate ethanol from the fermented mixture.