(I) 1,2-Dihydroxy benzene
(II) 1,3-Dihydroxy benzene
(III) 1,4-Dihydroxy benzene
(IV) Hydroxy benzene
The increasing order of boiling points of the above-mentioned alcohols is:

1,2-Dihydroxybenzene, 1,3-Dihydroxy benzene, 1,4-Dihydroxy benzene, Hydroxy benzene. (i), (ii), (iii), (iv) The'increasing order of boiling points of the above mentioned alcohols is,

Ortho-dihydroxy benzene is :

Ortho-dihydroxy benzene is :

Draw 1,4-Dibromo- benzene