Chemistry - Redox Reactions Question with Solution | TestHub

In iodometric estimation of ${\mathrm{Cu}}^{2+}$ ion, the following reaction took place:

${\mathrm{Cu}}^{2+}+{\mathrm{I}}^{-}⟶{\mathrm{C}{\mathrm{u}}_2\mathrm{I}}_2+{\mathrm{I}}_2$ (Not balanced)

${\mathrm{I}}_2+{\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3⟶{\mathrm{Na}}_2{\mathrm{S}}_4{\mathrm{O}}_6+\mathrm{NaI}$ (Not balanced)

If 100 mL of ${\mathrm{CuSO}}_4$ solution added to excess KI requires 50 mL of 0.2 M ${\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3$,

the molarity of ${\mathrm{CuSO}}_4$ solution is: