$CH_3-CN$ $\xrightarrow{H_2O/H^{+}} X$ $\xrightarrow{C_6H_5OH/H^{+}} Y$; $Y$ is

The reagent$(s)$ required for the following conversion are:

Provide identification tests for the following pairs of compounds:
$(1)$ Phenol and carboxylic acid
$(2)$ Formic acid and acetic acid
$(3)$ Acetic acid and ethanol
$(4)$ Acetic acid and acetone
$(5)$ Aldehyde and ketone
$(6)$ Acetaldehyde and acetone
$(7)$ Acetaldehyde and formaldehyde
$(8)$ Benzaldehyde and acetaldehyde

What are $\underline{A}, \underline{B}, \underline{C}$ in the following reactions?
$(I)$ $(CH_3 CO_2)_2 Ca \stackrel{\Delta}{\longrightarrow} \underline{A}$
$(II)$ $CH_3 CO_2 H \underset{\text{Red P}}{\stackrel{HI}{\longrightarrow}} \underline{B}$
$(III)$ $2 CH_3 CO_2 H \stackrel{P_4 O_{10}}{\longrightarrow} \underline{C}$
$\underline{A} \quad \underline{B} \quad \underline{C}$

Consider the following reaction scheme and choose the correct option for the major products $Q$,$R$ and $S$.

Ester and acetamide are distinguished by