Question

Identify oxidation number of Sulphur respectively in \(\text{SO}_2\) and \(\text{SO}_4^{2-}\) .

• A. \(+6,+4\)
• B. \(+4,+6\)
• C. \(+4,+3\)
• D. \(+3,+4\)

Hint:

Fix oxygen at -2 and make the sum equal the total charge.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The sum of oxidation numbers of all atoms in a species equals its charge. Oxygen is -2 here.

Step 2: Oxidation number in sulphur dioxide:
Let the oxidation number of S be \(x\): \(x + 2(-2) = 0\), so \(x = +4\).

Step 3: Oxidation number in the sulphate ion:
\(x + 4(-2) = -2\), so \(x = +6\).

Final Answer:
Sulphur has oxidation numbers +4 and +6, option (B). Option (A) reverses the order, while +3 does not occur in either. \[ \boxed{+4,\ +6} \]