Question

When $C _{2} H _{2}, CH _{4}$ and $C _{2} H _{4}$ pass through a test tube which has ammonical $Cu _{2} Cl _{2}$, find out which gas comes out unaffected from test tube?

• A. $C _{2} H _{2}$ and $CH _{4}$
• B. $C _{2} H _{2}$ and $C _{2} H _{4}$
• C. $C _{2} H _{4}$ and $CH _{4}$
• D. $C _{2} H _{2}$

Answer 1

Answer: (C)

$C _{2} H _{2}$ forms copper acetylide with ammonical $Cu _{2} Cl _{2}$ $ Cu _{2} Cl _{2}+2 NH _{4} OH \rightarrow Cu _{2} O + H _{2} O +2 NH _{4} Cl $ $ Cu _{2} O + C _{2} H _{2} \rightarrow \underset{\text{(copper acetylide)}}{Cu _{2} C _{2}}+ H _{2} O$