In the Liebermann’s nitroso reaction,the changes in the colour of phenol occur as:

An organic compound $A$ with empirical formula $C_6H_6O$ gives a sooty flame on burning. Its reaction with bromine solution in a low polarity solvent results in a high yield of $B$. $B$ is:

The increasing order of acidity among phenol,$p-$methylphenol,$m-$nitrophenol and $p-$nitrophenol is

The reaction of concentrated $HNO_3$ with phenol forms:

The major product of the following reaction sequence is:
Aniline $\xrightarrow[(i) NaNO_2, HCl, 273-278K]{(ii) H_2O, warm} \text{Product}$ $\xrightarrow[(iv) NaOH]{(iii) Br_2, (excess)} \text{Product}$ $\xrightarrow{(v) CH_3I} \text{Final Product}$

Which product is obtained when chlorobenzene is reacted with $6-8\%$ aqueous $NaOH$ at $633\,K$ temperature and $300\,bar$ pressure in the presence of an acid catalyst?