Sodium chloride is subjected to chloralkali process to manufacture sodium hydroxide. Chlorine and hydrogen gas are formed during this process. $$2 mathrm{NaCl}+2 mathrm{H}_{2} mathrm{O} \rightarrow 2 mathrm{NaOH}+mathrm{Cl}_{2}+mathrm{H}_{2}$$ Chlorine reacts with lime water to give bleaching powder. $$mathrm{Ca}(mathrm{OH})_{2}+mathrm{Cl}_{2} \rightarrow mathrm{CaOCl}_{2}+mathrm{H}_{2} mathrm{O}$$ X is chlorine. Y is bleaching powder.