Q. Assuming complete ionization, same moles of which of the following compounds will require the least amount of acidified $KMnO_4$ for complete oxidation?
A) $FeC_2O_4$
B) $Fe(NO_2)_2$
C) $FeSO_4$
D) $FeSO_3$
Explanation
[Solution] Electrons lost per formula unit: $FeC_2O_4$ 3, $Fe(NO_2)_2$ 5, $FeSO_4$ 1 ($Fe^{2+} \rightarrow Fe^{3+}$ only), $FeSO_3$ 3. $FeSO_4$ needs the least $KMnO_4$. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.