Chloride of an element $\mathrm{A}$ gave a neutral solution in water. In the periodic table, the element $\mathrm{A}$ belongs to

The element belongs to the first group, the reaction of metal (A) of first group with chlorine is:

$2\mathrm{A}+{\mathrm{Cl}}_2\to 2\mathrm{ACl}$
Reaction of MCl with water is:

$\mathrm{ACl}+{\mathrm{H}}_2\mathrm{O}\to \underset{\mathrm{neutral} \mathrm{solution}}{\underbrace{\underset{\mathrm{strong} \mathrm{acid}}{\mathrm{HCl}}+\underset{\mathrm{strong} \mathrm{base}}{\mathrm{AOH}}}}$