Formation of ethylene from acetylene is an example of

The compound belonging to the homologous series of ethyne is .........

$A$ 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:

$CH_3-CH_2-C \equiv CH \xrightarrow{R, H_2O} \text{Butanone}$. $R$ is:

The reagent which could distinguish between $1-$hexyne and $1-$hexene is

Identify the reagent used for the following conversion: $CH_3-C \equiv C-CH_3 \longrightarrow \text{cis-but-2-ene}$