Calculate the value of $x + \text{molecular mass of } (C)$,where $x$ is the number of moles of $PhMgBr$ consumed in reaction $(a)$ and $(C)$ is the gas evolved in reaction $(b)$.
$(a)$ $3\text{-hydroxy-5-formylbenzoyl chloride} + x \ PhMgBr \xrightarrow{\text{excess}} (A)$
$(b)$ $2,5\text{-dioxocyclohexanecarboxylic acid} \xrightarrow{\Delta} (B) + (C) \uparrow$

Identify the major product of the reaction when the given compound is hydrolyzed and heated strongly.

If $(\pm)$ $2$-methylbutanoic acid is esterified by reaction with $(\pm)$ $2$-butanol,how many optically active compounds will be present in the final equilibrium reaction mixture?

Statement $(A)$: Carboxylic acid can be obtained by the reaction of $R-C \equiv N$ with $H_3O^+$ under mild reaction conditions.
Statement $(B)$: Hydrolysis of $R-C \equiv N$ in alkaline aqueous medium gives $R-COONa$ and $NH_3$ as products.
The correct answer is:

Which of the following reactions produce ethyl cyanide $(CH_3 CH_2 CN)$ as a major product?
$1.$ $CH_3 CH_2 CH=NOH \xrightarrow{(CH_3 CO)_2 O} CH_3 CH_2 CN$
$2.$ $CH_3 CH_2 Cl \xrightarrow{\text{Ethanolic } KCN} CH_3 CH_2 CN$
$3.$ $CH_3 CH_2 Cl \xrightarrow{\text{Ethanolic } AgCN} CH_3 CH_2 NC$
$4.$ $CH_3 CH_2 CON(CH_3)_2 \xrightarrow[\text{Pyridine, } 70^{\circ} C]{C_6 H_5 SO_2 Cl} CH_3 CH_2 CN$

The product of the following reaction is :