Number of $\pi$-bonds present in $B.H.C.$ ($Benzene$ $hexachloride$) are

Benzene is obtained from

Which of the following represents $H$ückel's rule for aromaticity?

Assertion : Tropylium cation is aromatic in nature.
Reason : The only property that determines its aromatic behaviour is its planar structure.

For the electrophilic substitution reaction involving nitration,which of the following sequences regarding the rate of reaction is true?

How many hydroxy groups are present in hydroxyquinol?