Question

H2O2(aq)+ClO4−(aq)→ClO2−(aq)+O2(g)

Express your answer as a net ionic equation including phases in basic solution

Answer 1

H

2

O

2

(aq)+ClO

4

−

(aq)⟶O

2

(g)+ClO

2

−

(aq)

All atoms except H and O are balanced.

The oxidation number of Cl changes from 7 to 3. The change in the oxidation number is 4.

The oxidation number of O changes from -1 to 0. The change in oxidation number per O atom is 1.

Total change in the oxidation number for 2 oxygen atoms is 2.

To balance the increase in oxidation number with decrease in the oxidation number, multiply H

2

O

2

and O

2

with coefficients 2.

2H

2

O

2

(aq)+ClO

4

−

(aq)⟶2O

2

(g)+ClO

2

−

(aq)

To balance O atoms, add 2 water molecules on RHS.

2H

2

O

2

(aq)+ClO

4

−

(aq)⟶2O

2

(g)+ClO

2

−

(aq)+2H

2

O(l)

The oxygen atoms are already balanced.

This is the balanced chemical equation