State the oxidation states for sulfur in the following compounds: a) SO3 b) H2SO4

Answer 1

To answer this question, let's first look at the atoms in the compounds for which we know the oxidation number. Oxygen has an oxidation number of 2-. So, in SO3, in order to create a net neutral, or zero charge, the S must have an oxidation number 6+ to cancel out the 3*(-2)= -6 of the oxygen in the compound.

Hydrogen has an oxidation number of 1+. In H2SO4, the hydrogen atoms create 2*(+1) charge and the oxygen atoms create 4*(-2) charge. The S must have an oxidation number of 6+ that will cancel out these charges, 2*(+1) + 4*(-2) = -6.

Answer 2

SO₃ 6+

H₂SO₄ 6+ also