When phenol is heated with phthalic anhydride in presence of conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$, an important acid-base indicator is formed. Identify its structure.

What is $\text{Z}$ in the following sequence of reactions?
$\mathrm{Phenol}\stackrel{\mathrm{Zn} \mathrm{dust}}{\to }\mathrm{X}\stackrel{{\mathrm{CH}}_3\mathrm{Cl}/\mathrm{Anhydrous} {\mathrm{AlCl}}_3}{\to }\mathrm{Y}\stackrel{\mathrm{Alkaline} {\mathrm{KMnO}}_4}{\to }\mathrm{Z}$

Assertion$\left(\mathrm{A}\right):-\mathrm{OH}$ group of phenol is ortho, para directing in electrophilic substitutions

Reason $\left(\mathrm{R}\right):-\mathrm{OH}$ group stabilises the arenium ion formed by the ortho, para attack of the electrophile

The correct answer is

The major product $\left(\mathrm{P}\right)$ formed in the following reaction is

The conversion of phenol into salicylic acid is done via_____reaction.

Ortho-salicylic acid is frequently used as a precursor for the preparation of aspirin. Which of the following reactions can be used to prepare ortho-salicyclic acid from phenol?