The compound `C_8H_9Cl(A)` on treatments with KCN followed by hydrolysis gives `C_9H_10O_2(B)`.Ammonium salt of B on dry distillation yields C.Which reacts with alkaline solution of bromine to gives `C_8H_11N`.(D),Another compound E `(C_6H_10O)` is obtained by the action of nitrous acid on D. or by the action of aquouspotash on A,E on oxidation gives `F(C_8H_10O)` Which gives the inner anhydride G on heating.
The compound D is reaction with `CHCl_3+NaOH` gives a compound H.The structure of H.

Explanation

`D.U` in `(A) = ((2n_(C) + 2) + 2_(Cl) - n_(H))/(2)`
`= ((2xx8+2)+1-9)/(2) = 5^(@)`
`5 D.U` and `(C:H = 1:1)` suggest benzene ring in `(A)`, with two `(Me)` groups or one `(Et)` group.
Reaction with `KCN` shows that `(A)` contain `1^(@) RCl` group (i.e., it contains `(-CH_(2)Cl)` group in the side chain and one `(Me)` group in the ring).
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Formation of `(G)`, an anjydride shows that `(Me)` groupas is at ortho-postion. orthos-diacid froms anhydride.
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