$ClCH_2-CH_2Cl$ $\xrightarrow[(ii) NaNH_2]{(i) Alc. KOH}$ $A$ $\xrightarrow{\text{Red hot Fe tube}}$ $B$
Identify product $B$ in the above reaction sequence.

The following reaction is given:
$\xrightarrow{\text{Electrolysis}} A$
$A$ is

The increasing order of the rate of reaction with $HNO_3 / H_2SO_4$ is:

Identify the product $A$ in the following reaction:
$C_6H_6 + CH_2Cl_2 \xrightarrow{\text{Anhy. } AlCl_3} A$

What is the ratio of glyoxal to pyrualdehyde obtained in the ozonolysis of $o-xylene$ as shown in the reaction below?
$o-Xylene$ $\xrightarrow[{(2) Zn}]{{(1) O_3}} CHO-CHO \text{ (Glyoxal)} + CH_3CO-COCH_3 \text{ (2,3-Butanedione)} + CH_3CO-CHO \text{ (Pyrualdehyde)}$

The number of $-CH_2-$ (methylene) groups in the product formed from the following reaction sequence is. . . . . . .