Benzene is the polymer of

$2$-Hexyne reacts with $.......$ to give $trans-2$-hexene.

Acetylenic hydrogens are acidic because

The bond length between the hybridized carbon atom and another carbon atom is minimum in:

The major product of the following reaction is $P$. Number of oxygen atoms present in product $P$ is $. . . . . . . . . . . (nearest integer)$.

$2-$pentyne on reaction with sodium in liquid ammonia produces compound $A$. What is $A$?