Question

Identify the correct coefficients (a), (b), (c) and (d) in the following equations
\[ \text{i) } xMnO_4^- + (a)\,SO_3^{2-} + (b)\,H^+ \rightarrow xMn^{2+} + (a)\,SO_4^{2-} + (c)\,H_2O \]
\[ \text{ii) } (c)\,S_2O_3^{2-} + (d)\,MnO_4^- + H_2O \rightarrow (d)\,MnO_2 + (b)\,SO_4^{2-} + xOH^- \]

• A. \( (a)=3,\,(b)=8,\,(c)=6,\,(d)=6 \)
• B. \( (a)=5,\,(b)=6,\,(c)=3,\,(d)=8 \)
• C. \( (a)=2,\,(b)=8,\,(c)=4,\,(d)=4 \)
• D. \( (a)=2,\,(b)=6,\,(c)=6,\,(d)=5 \)

Hint:

Always identify medium (acidic/basic) before balancing redox reactionsPermanganate behaves differently in different media.

Answer 1

The Correct Option is B