Rules to Remember
* Oxygen usually has an oxidation state of -2, unless it's in a peroxide (like H₂O₂) where it's -1.
* The sum of the oxidation states in a polyatomic ion must equal the charge of the ion.
Applying the Rules
1. Oxygen: In ClO⁻, the oxygen atom has an oxidation state of -2.
2. Charge: The ion has a charge of -1.
3. Solving for Cl: Let x be the oxidation state of Cl. We can set up the equation:
x + (-2) = -1
4. Simplify and Solve:
x - 2 = -1
x = +1
Therefore, the oxidation state of Cl in ClO⁻ is +1.
