What is the oxidation number of sulfur in the HSO4
The Correct Answer and Explanation is:
The oxidation number of sulfur in the hydrogen sulfite ion (HSO₃⁻) is +4.
Explanation:
To determine the oxidation number of sulfur in HSO₃⁻, we follow these steps:
- Assign known oxidation numbers:
- Hydrogen (H) always has an oxidation number of +1 in compounds.
- Oxygen (O) usually has an oxidation number of -2 in most compounds.
- The oxidation number of sulfur (S) is unknown and will be determined.
- Set up the equation: The total charge of the polyatomic ion HSO₃⁻ is -1, meaning the sum of oxidation numbers of all atoms must equal -1.Let x be the oxidation number of sulfur. Using oxidation numbers:
(+1)+(x)+3(−2)=−1(+1) + (x) + 3(-2) = -1
- Solve for x:
1+x−6=−11 + x – 6 = -1
x−5=−1x – 5 = -1
x=+4x = +4
Thus, the oxidation number of sulfur in HSO₃⁻ is +4.
Why is this important?
The oxidation number reflects how electrons are distributed in a compound, helping chemists understand its chemical properties, reaction behavior, and potential redox activity. In this case, sulfur in HSO₃⁻ is in the +4 oxidation state, meaning it can either gain or lose electrons depending on its chemical reaction, making it an essential intermediate in oxidation and reduction processes.
