Question

A mixture of ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}$, ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}$ and ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{2}}}$ is bubbled through alkaline solution of copper (I) chloride, contained in Woulf’s bottle. The gas coming out is:
A.Original mixture
B.${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}$
C.${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}$ and ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}$ mixture
D.${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}$ and ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{2}}}$

Answer 1

Hint:Alkynes react with copper (I) chloride and form a red-brown coloured precipitate. Alkenes and alkanes do not react with copper (I) chloride.

Complete step by step answer:
When a mixture of ethyne $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{2}}}} \right)$, ethene $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}} \right)$ and ethane $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}} \right)$ is bubbled through an alkaline solution of copper (I) chloride:
Ethyne $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{2}}}} \right)$ reacts with the alkaline solution of copper (I) chloride.
Ethene $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}} \right)$ and ethane $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}} \right)$ do not react with the alkaline solution of copper chloride and come out as gas.
Thus, the gas coming out is ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{6}}}$ and ${{\text{C}}_{\text{2}}}{{\text{H}}_{\text{4}}}$ mixture.

Thus, the correct option is option (C).

Additional Information:
Ethane and ethene do not react with the alkaline solution of copper (I) chloride as they do not have acidic hydrogen.

Note: The reaction of ethyne $\left( {{{\text{C}}_{\text{2}}}{{\text{H}}_{\text{2}}}} \right)$ with an alkaline solution of copper (I) chloride is as follows:

Copper (I) acetylide is produced in the reaction. Copper (I) acetylide is a brown colored precipitate.