Find the number of reactions where ${\mathrm{CaCl}}_2$ is the product from the following :

(i)$\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{FeSO}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4\to$

(ii)$\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{H}}_2{\mathrm{SO}}_4\to$

(iii)$\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{CaCO}}_3\to$

(iv)$\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{Na}}_3{\mathrm{AsO}}_4\to$

(v) $\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{NH}}_3\to$

Out of the given five reactions, three of them lead to the formation of calcium chloride.

$\text{ (i) }\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+2{\mathrm{FeSO}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{Fe}}_2{\left({\mathrm{SO}}_4\right)}_3+{\mathrm{CaCl}}_2+{\mathrm{H}}_2\mathrm{O}$

The reaction of bleaching powder with Iron(ii) sulphate and Sulphuric acid gives Calcium chloride, Iron (III)sulphate and water.

$\text{ (iv) }\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+{\mathrm{Na}}_2{\mathrm{AsO}}_3\to {\mathrm{CaCl}}_2+{\mathrm{Na}}_3{\mathrm{AsO}}_4$

Calcium chloride along with sodium arsenate is formed when Sodium arsenite reacts with bleaching powder as shown above.

$\text{ (v) }\mathrm{Ca}\left(\mathrm{OCl}\right)\mathrm{Cl}+2{\mathrm{NH}}_3\to {\mathrm{CaCl}}_2+3{\mathrm{H}}_2\mathrm{O}+{\mathrm{N}}_2$

Bleaching powder in reaction with ammonia gives calcium chloride, nitrogen gas, and water as products.

 $3$ of the given reaction gives ${\mathrm{CaCl}}_2$ as the product.

Therefore the correct answer is $3$.