REDOX REACTIONS

What is the oxidation number of Cl_²?

• 0

• +1

• +2

• -1

What is the oxidation number of Sulfide ion, S^2-?

• -2

• -1

• 0

• +2

What is the oxidation number of oxygen in H₂O?

• 0

• +1

• +2

• -2

What is the oxidation number of phosphorus in phosphate ion, PO₄^3-?

• 0

• +1

• +5

• -5

What is the oxidation number of sulfur in H₂SO₄?

• 0

• +1

• +4

• +6

Which of these chemical reactions is an oxidation-reduction reaction?

• CO₂ + H₂O -> H₂CO₃

• Fe + S -> FeS

• AgNO₃ + NaCl ->AgCl + NaNO₃

• H₂SO₄ + 2NaOH -> Na₂SO₄ + 2H₂O

In which substance does bromine have an oxidation number of +1?

• Br₂

• HBr

• HBrO

• HBrO₂

What happens to the oxidising agent in an oxidation-reduction reaction?

• It is oxidised as it gains electrons.

• It is oxidised as it loses electrons.

• It is reduced as it gains electrons.

• It is reduced as it loses electrons.