The volume, in mL , of $0.02 \mathrm{M} \mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ solution requ

Question

The volume, in mL , of $0.02 \mathrm{M} \mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ solution required to react with 0.288 g of ferrous oxalate in acidic medium is $\qquad$ .\ (Molar mass of $\mathrm{Fe}=56 \mathrm{~g} \mathrm{~mol}^{-1}$ )\

Professor PC Thomas Classes · Answer

(50) : $\mathrm{FeC}_{2} \mathrm{O}_{4}+\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-} ightarrow \mathrm{Fe}^{3+}$ $+\mathrm{CO}_{2}+\mathrm{Cr}^{3+}$\ $	herefore \quad \frac{M_{1} V_{1}}{3}=\frac{M_{2} V_{2}}{6}$\ $\frac{0.02 	imes V_{1}}{3}=\frac{0.288}{144 	imes 6} 	imes 1000$\ $V_{1}=\frac{0.288}{144 	imes 6} 	imes \frac{1000 	imes 3}{0.02}=50 \mathrm{~mL}$\