In CaF2, the oxidation number of Ca is , and that of F is . In H2SO4, the oxidation number of H is , that of S is , and that of O is . In CaSO4, the oxidation number of Ca is , that of S is , and that of O is . In HF, the oxidation number of H is , and that of F is .
In CaF2, the oxidation number of Ca is:+2
In H2SO4, the oxidation number of H is:+1
In CaSO4, the oxidation number of Ca is:+2
In HF, the oxidation number of H is:+1