$$ \text { Which of the following is NOT phenol? } $$

Identify ' $A$ ' in the following reaction.

A + Acetic anhydride $\xrightarrow{\mathrm{H}^{+}}$Aspirin + Acetic acid

Identify the product ' $B$ ' in the following sequence of reactions.

$$ \text { Ethanenitrile } \xrightarrow{\mathrm{SnCl}_2 . \mathrm{HCl}^{\mathrm{}}} \mathrm{~A} \xrightarrow{\mathrm{H}_3 \mathrm{O}^{+}} \mathrm{B}+\mathrm{NH}_4 \mathrm{Cl} $$

Calculate work done if 1 mole of an ideal gas expands isothermally from $2 \mathrm{dm}^3$ to $2.8 \mathrm{dm}^3$ against constant external pressure 1 atm .