The number of chlorine atoms present in the organic products X and Y of the following reactions, respectively, are :
\(C _6 H _6+6 Cl _2 \xrightarrow[\text { dark, cold }]{\text { Anhydr. } AlCl _3} X\)
\(C _6 H _6+3 Cl _2 \xrightarrow[500 K]{ UV } Y\)

(C) 6 and 6
Reaction 1 is an electrophilic aromatic substitution. Benzene reacts with excess chlorine in the presence of anhydrous \(AlCl _3\) (a Lewis acid) to form hexachlorobenzene ( \(C _6 Cl _6\) ).
\(C_6 H_6+6 Cl_2 \xrightarrow[\text { dark, cold }]{\text { Anhydr. } AlCl_3} C_6 Cl_6+6 HCl\)
The organic product X is hexachlorobenzene, which contains 6 chlorine atoms.Reaction 2 is a free radical addition reaction. Benzene reacts with chlorine in the presence of UV light to form benzene hexachloride \(\left( C _6 H _6 Cl _6\right)\), also known as gammaxene or lindane.
\(C_6 H_6+3 Cl_2 \xrightarrow[500 K]{UV} C_6 H_6 Cl_6\)
The organic product Y is benzene hexachloride, which contains 6 chlorine atoms.Therefore, the number of chlorine atoms in both X and Y is 6.