Write the reaction of acetaldehyde with sodium bisulphite.

The compound A in the following reactions is:

$$\begin{gathered} \mathrm{A} \underset{\left(\mathrm{ii}\right) \mathrm{Conc}. {\mathrm{H}}_2{\mathrm{SO}}_4/∆}{\overset{\left(\mathrm{i}\right) {\mathrm{CH}}_3\mathrm{MgBr}/{\mathrm{H}}_2\mathrm{O}}{\to }} \\ \mathrm{B} \underset{\left(\mathrm{ii}\right) \mathrm{Zn}/{\mathrm{H}}_2\mathrm{O}}{\overset{\left(\mathrm{i}\right) {\mathrm{O}}_3}{\to }}\mathrm{C}+\mathrm{D} \end{gathered}$$

The increasing order of the following compounds towards $\mathrm{HCN}$ addition is :

(i)   (ii)  (iii)(iv)   

For the reaction-

 rate of reaction is faster, when $\mathrm{Z}$ is-

One of the products of the following reaction is $\mathrm{P}.$

Structure of $\mathrm{P}$ is

The major products $\mathrm{P}$ and $\mathrm{Q}$ in the following reaction sequence are

The increasing order of the reactivity of the following compounds in nucleophile addition reaction is:

Propanal, Benzaldehyde, Propanone, Butanone

The correct order of reactivity for the addition reaction of the following carbonyl compounds with ethylmagnesium iodide is