Upon the addition of water, As2O3 is converted to H3AsO3. During the titration H3AsO3 is oxidized to H3AsO4 and MnO4 - is reduced to Mn2. Write a balanced net ionic equation for the reaction

5H3AsO3 (aq) + 2MnO4 - (aq) + 6H + (aq) → 5H3AsO4 (aq) + 2Mn2 + (aq) + 3H2O (aq)

Explanation:

Every net balanced ionic equation is composed of a union of two half equations;

The oxidation half equation (indicating electron loss) and the reduction half equation (indicating electron gain). Remember that redox reactions is a process in which electrons are lost and gained by chemical species simultaneously. One specie looses electrons in the oxidation half equation while the other specie gains electrons in the reduction half equation.

The balanced redox reaction equation shows the overall redox process and shows at a glance the total number of elect tribe lost or gained in the redox process. The overall redox reaction equation for the titration described in the question is;

5H3AsO3 (aq) + 2MnO4 - (aq) + 6H + (aq) → 5H3AsO4 (aq) + 2Mn2 + (aq) + 3H2O (aq)