Electrophilic substitution reaction in phenol takes place at:

The electrophile involved in the reaction shown below is:
$C_6H_5OH + CHCl_3 + NaOH \rightarrow C_6H_4(ONa)CHO$

The order of reactivity of phenol $(I)$,nitrobenzene $(II)$,and benzene $(III)$ towards nitration is:

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

The phenolic group can be identified by a positive:

The reaction shown in the figure is known as: