The reagent which is used to distinguish between propene and propyne is

Consider the following sequence,where $A$ can be:
$A$ $(C_{3}H_{6}Cl_{2})$ $\xrightarrow[2. \, H^{+} \, (mild)]{1. \, \text{alcoholic } KOH / \Delta, \text{ followed by } NaNH_{2} / \Delta}$ $B$ $\xrightarrow[H_{2}O_{2} / OH^{-}]{B_{2}H_{6}}$ $C$
$A$ $\xrightarrow{aq. \, KOH \, (excess)}$ $C$
Identify $A$.

Provide the primary information about alkynes.

$A$ compound $C_5H_8$ gives a white precipitate with ammoniacal $AgNO_3$. It yields $(CH_3)_2CHCOOH$ upon oxidation with hot alkaline $KMnO_4$. The compound is:

In which of the following compounds is the bond length between an $sp^3$ hybridized carbon and an adjacent carbon atom the shortest?

Which of the following does not belong to the same homologous series?