Table of contents

This is an oxidation-reduction (redox) reaction:

SIV - 2 e- → SVI (oxidation)

MgII + 2 e- → Mg0 (reduction)

MgSO3 is a reducing agent, MgSO3 is an oxidizing agent.

Input interpretation

MgSO3 → Mg + SO3

Magnesium sulfur trioxide

Balanced equation

Balance the chemical equation algebraically:

MgSO3 → Mg + SO3


Add stoichiometric coefficients, c2, to the reactants and products:

c1MgSO3 → c2 Mg + c3SO3

Set the number of atoms in the reactants equal to the number of atoms in the products for Mg, S and O:

Mg: c1 = c2

S: c1 = c3

O: 3c1 = 3c3

Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:

c1=1 c2=1

c3 = 1

Substitute the coefficients into the chemical reaction to obtain the balanced equation:


MgSO3 → Mg + SO3