Benzne reacts with sulphuric acid to form benzenesulphonic acid, only when the sulphuric acid is

Options

A. cold and dilute
B. hot and dilute
C. hot and concentrated
D. mixed with `HNO_(3)`

Answer

C

Explanation

Sulphonation of benzene is usually carried out with fuming sulphuric acid at room temperature sulphonation also takes place in concentrated `H_(2)SO_(4)` but more slowly thus we must use hot and conc. `H_(2)SO_(4)`.