What is the oxidation state of Sin SO 3 ^ 2-?

Oxidation state of S in SO3^2 - is + 4

Explanation:

S in SO3^2-=

S = ?

O = - 2

S + 3 moles of O * - 2 = - 2

S + (-6) = - 2 (it has charge - 2)

S - 6 = - 2

S = - 2 + 6

S = + 4

Note, the sign is very important

Don't confuse SO3 together with SO3^2-, the oxidation state of S in SO3 is + 6, how?

S = ?

O = - 2

S + 3 * - 2 = 0 (because it has no charge)

S - 6 = 0

S = + 6

And in SO3^2-

S = + 4

The difference is that one has charge SO3^2 - and the other doesn't SO3.