Question

What is the oxidation number of sulfur in \( \text{H}_2\text{SO}_4 \)?

• A. \( +6 \)
• B. \( +2 \)
• C. \( 0 \)
• D. \( -2 \)

Hint:

Remember: The sum of oxidation numbers in a neutral molecule is always zero. For polyatomic ions, the sum equals the charge of the ion.

Answer 1

The Correct Option is A

Step 1: Assign oxidation numbers to the elements in \( \text{H}_2\text{SO}_4 \)
The oxidation number of hydrogen \( \text{H} \) is \( +1 \), and the oxidation number of oxygen \( \text{O} \) is \( -2 \).
Step 2: Use the rule for the sum of oxidation numbers
The sum of the oxidation numbers in a neutral compound must be zero. The oxidation numbers of the two hydrogen atoms contribute \( +2 \), and the oxidation numbers of the four oxygen atoms contribute \( 4 \times (-2) = -8 \).
Let the oxidation number of sulfur be \( x \). \[ 2 \times (+1) + x + 4 \times (-2) = 0 \] \[ 2 + x - 8 = 0 \] \[ x = +6 \] Answer: Therefore, the oxidation number of sulfur in \( \text{H}_2\text{SO}_4 \) is \( +6 \). So, the correct answer is option (1).