$But-1-yne$ reacts with cold alkaline $KMnO_4$ to produce:

An unsaturated hydrocarbon $X$ on ozonolysis gives $A$. Compound $A$ when warmed with ammoniacal silver nitrate forms a bright silver mirror along the sides of the test tube. The unsaturated hydrocarbon $X$ is ..... .

Give the method of preparation of ethyne (acetylene) from vicinal dihalides.

The major products $P$ and $Q$ in the following reactions,respectively,are:
$H_3C-C \equiv C-CH_2CH_3 \xrightarrow{H_2, \text{Lindlar's Catalyst}} P$
$H_3C-C \equiv C-CH_2CH_3 \xrightarrow{Na/\text{liquid } NH_3} Q$

Which product is obtained from the reaction of calcium carbide with water?

When $CH_3CH_2CH_2CHCl_2$ is treated with $2 \ g$ equivalent of $NaNH_2$,the product formed is: