Identify the product obtained when $2$-chlorobutane is heated with an aqueous solution of potassium hydroxide.

$A$ solution of $1$-chloro-$1$-phenylethane in toluene undergoes direct racemization in the presence of a small amount of $SbCl_5$ due to the formation of:

Identify $A, B, C, D, E, R$ and $R^1$ in the following reactions:
$Cyclohexyl-Br + Mg$ $\xrightarrow{dry\,ether} A$ $\xrightarrow{H_2O} B$
$R-Br + Mg$ $\xrightarrow{dry\,ether} C$ $\xrightarrow{D_2O} CH_3-CH(D)-CH_3$
$CH_3-C(CH_3)_2-C(CH_3)_2-CH_3 \xleftarrow{Na/ether} R^1-X$ $\xrightarrow{Mg} D$ $\xrightarrow{H_2O} E$

Which of the following compounds will give a racemic mixture by $S_N1$ reaction?

The main product formed when ethylbenzene reacts with $Cl_2$ in the presence of light is:

Give the chemical reactions for the following conversions:
$(1)$ Tertiary butyl alcohol from $1-$bromo$-2-$methylpropane
$(2)$ Ethanol from $1,2-$dibromoethane