$p$-Toluidine reacts with benzene diazonium chloride to form a compound,which on boiling with $aq. H_2SO_4$ gives ........ products.

$(a) \, CH_3CONH_2 + KOH + Br_2 \rightarrow$
$(b) \, CH_3COOH + \text{Soda lime} \rightarrow$
$(c) \, CH_3COOAg + Br_2 \rightarrow$
What is the common feature in the above three reactions?

In a reaction of aniline,a coloured product $C$ was obtained as shown below:
$A$ $\xrightarrow{NaNO_2/HCl} B$ $\xrightarrow{N,N-dimethylaniline, \text{cold}} C$
The structure of $C$ would be:

You have been given four bottles marked $A, B, C$ and $D$ each containing one of the organic compounds given below:

$I: C_6H_5CH_2NH_2$	$II: C_6H_5CH_2COOH$
$III: C_6H_5CH_2CH_3$	$IV: C_6H_5CH_2CH(NH_2)COOH$

The following observations were made:
$(i)$ The compound in bottle $A$ did not dissolve in either $1 \ N \ NaOH$ or $1 \ N \ HCl$.
$(ii)$ The compound in bottle $B$ dissolved in $1 \ N \ NaOH$ but not in $1 \ N \ HCl$.
$(iii)$ The compound in bottle $C$ dissolved in both $1 \ N \ NaOH$ and $1 \ N \ HCl$.
$(iv)$ The compound in bottle $D$ did not dissolve in $1 \ N \ NaOH$ but dissolved in $1 \ N \ HCl$.
$(a)$ Indicate the compounds in: bottle $A = \dots$,bottle $B = \dots$,bottle $C = \dots$ and bottle $D = \dots$.
$(b)$ The compound with the highest solubility in distilled water is .......

Complete the following reactions:
$(i)$ $C_{6}H_{5}NH_{2} + CHCl_{3} +$ alc. $KOH \rightarrow$
$(ii)$ $C_{6}H_{5}N_{2}Cl + H_{3}PO_{2} + H_{2}O \rightarrow$
$(iii)$ $C_{6}H_{5}NH_{2} + H_{2}SO_{4}$ (conc.) $\rightarrow$
$(iv)$ $C_{6}H_{5}N_{2}Cl + C_{2}H_{5}OH \rightarrow$
$(v)$ $C_{6}H_{5}NH_{2} + Br_{2(aq)} \rightarrow$
$(vi)$ $C_{6}H_{5}NH_{2} + (CH_{3}CO)_{2}O \rightarrow$
$(vii)$ $C_{6}H_{5}N_{2}Cl \xrightarrow[(ii) NaNO_{2}/Cu, \Delta ]{(i) HBF_{4}}$

An organic compound $A$ on reduction gives compound $B$,which on reaction with trichloromethane and caustic potash forms $C$. The compound $C$ on catalytic reduction gives $N$-methylbenzenamine. The compound $A$ is,