7-6 Balance redox half reactions in aqueous solution

7-6-1. Consider the half-reaction (unbalanced) in acidic solution:
HClO₂(aq) ==> Cl₂(g)
When this half reaction is balanced using the smallest set of whole number coefficients, what is the coefficient of H⁺(aq) and how many electrons are involved?


7-6-2. Consider the half-reaction (unbalanced) in basic solution:
ClO₂^-(aq) ==> Cl₂(g)
When this half reaction is balanced using the smallest set of whole number coefficients, what is the coefficient of OH^-(aq) and how many electrons are involved


7-6-3. When the following half reaction
H₂SO₃(aq) ==> SO₄ ^2-
is balanced in acidic solution using the smallest of whole numbers, what is the coefficient of H2O and how many electrons are involved?
A. 1, 2 B. 1, 3 C. 2, 3 D. 3, 1




7-6-4. Which of the following is a reduction half reaction?

A.SO_{2 (g)} ==> SO₃^2-_(aq)
B.SO₄^2-_(aq) ==> SO₃^2-_(aq)
C.S^2-_(aq) ==> SO₃^2-_(aq)