Heating a mixture of silver powder and $CHCl_3$ yields which compound?

Which reagent can be used to distinguish between $1$-butyne and $2$-butyne?

In the reaction $x + H_2O \xrightarrow[H_2SO_4]{HgSO_4} CH_3-CO-CH_2-CH_3$,the reactant $x$ is:

What are $X$ and $Y$ respectively in the following reaction?
$Z$-product $\stackrel{Y}{\longleftarrow} 2$-butyne $\stackrel{X}{\longrightarrow} E$-product

The triple bond in ethyne $(C_2H_2)$ is formed from:

$(A)$ $\xrightarrow[dil. H_2SO_4]{HgSO_4} (B)$ $\xrightarrow{LiAlH_4} \underset{\text{racemic mixture}}{(C)}$
$\therefore$ reactant $(A)$ is