Chemistry - Redox Reactions Question with Solution | TestHub

An aqueous solution of ${\mathrm{FeCl}}_3$ obtained when an itched copper circuit board was washed required 40 mL of 0.1 M hydrazine hydrochloride for its reduction to ${\mathrm{Fe}}^{2+}$. During this process hydrazine gets converted to ${\mathrm{N}}_2$. How many mL of $\frac{2}{3}\mathrm{M}$ nitric acid is required for the re-oxidation of ${\mathrm{Fe}}^{2+}$ to ${\mathrm{Fe}}^{3+}$?

[Given: Nitric acid gets reduced to NO during this process.]