The gas evolved when ethyl amine reacts with sodium metal is

Which of the following substituents,when attached at the para-position of aniline,decreases its basicity?

Identify the reagents $(X, Y, Z)$ used in the conversion of $3$-methylaniline to $3$-nitrotoluene.

$(CH_3)_2CHCONH_2$ $\xrightarrow{Br_2/NaOH} A$ $\xrightarrow{COCl_2} B$. In this reaction sequence,$B$ is:

In the sequence of the following reactions,$X$ and $Y$ are respectively: $CH_3OH$ $\xrightarrow{HI} CH_3I$ $\xrightarrow{KCN} CH_3CN$ $\xrightarrow{\text{reduction}} X$ $\xrightarrow{HNO_2} Y$

Identify $X$ and $Y$ in the following reactions:
$Nitrobenzene \xrightarrow{Zn/NH_4Cl} X$
$Nitrobenzene \xrightarrow{Zn + KOH/C_2H_5OH} Y$