When a mixture of vapours of phenol and hydrogen is passed over nickel catalyst at $433 \ K$,the product obtained is

Explain the classification of phenols with examples.

Complete the following reaction: $C_6H_5OH + ArN_2^+Cl^- \xrightarrow{OH^-} ?$

The ascending order of acidity of the $-OH$ group in the following compounds is:
$A$. $Bu-OH$
$B$. $p$-nitrophenol
$C$. $p$-methoxyphenol
$D$. Phenol
$E$. $2,4$-dinitrophenol
Choose the correct answer from the options given below:

The order of acidic strength of $X, Y$ and $Z$ is:
Phenol reacts with dilute $HNO_3$ to form $X$ ($o$-nitrophenol) and $Y$ ($p$-nitrophenol). Phenol reacts with concentrated $HNO_3$ and $H_2SO_4$ to form $Z$ ($2,4,6$-trinitrophenol or picric acid).

Identify the solvent used in the bromination of phenol to obtain $2,4,6$-tribromophenol.