Question

4.
A mixture of methane, ethene and carbondioxide measuring 10 ml was exploded with excess of air.
After explosion there was a contraction of 17 ml and after treatment with KOH solution, there was a
further contraction of volume by 14 ml. What was the composition of the mixture? (Volume
measurements refer to same P-T conditions)​

Answer 1

Answer:

The contraction on cooling is due to the condensation of water vapour. Thus 17 ml of water are formed in the reaction.

The contraction in the volume of 14 ml is due to the dissolution of carbon dioxide gas. Hence, 14 g of carbon dioxide is present in the mixture after the explosion.

4.5ml

CH

4

→

4.5ml

CO

2

+

9ml

2H

2

O

4ml

C

2

H

4

→

8

2CO

2

+

8ml

2H

2

O

Hence, the composition of the mixture is 4.5 ml methane and 1.5 ml of carbon dioxide.