Answer:
Step-by-step explanation:
A) In H2SO4, the oxidation number of H is , that of S is , and that of O is .
In H₂SO₄ the oxidation sate of H is +1 (H₂= +2) that of sulfur is +6 and O is -2 (O₄= -8)
In SO₄ the oxidation state is -2, because negative and positive charges are not equal. That's why two hydrogen atoms are attached with one SO₄ to balance the charge.
B) In CaSO4, the oxidation number of Ca is , that of S is . , and that of O is .
In CaSO₄ the oxidation sate of Ca is +2 that of sulfur is +6 and O is -2 (O₄= -8)
In SO₄ the oxidation state is -2, because negative and positive charges are not equal. That's why one calcium atoms is attached with one SO₄ to balance the charge.
C) In HF, the oxidation number of H is , and that of F is .
In HF the oxidation state of hydrogen is +1 and that of fluorine is -1. Both form ionic compound.