Table of contents

This is an oxidation-reduction (redox) reaction:

6 Br0 + 6 e- → 6 Br-I (reduction)

2 Fe0 - 6 e- → 2 FeIII (oxidation)

Br2 is an oxidizing agent, Fe is a reducing agent.

Word equation

bromine + iron → iron(III) bromide

Input interpretation

Br2 + Fe → Febr3

Bromine iron iron(III) bromide

Balanced equation

Balance the chemical equation algebraically:

Br2 + Fe → Febr3

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

c1Br2 + c2 Fe → c3 Febr3

Set the number of atoms in the reactants equal to the number of atoms in the products for Br and Fe:

Br: 2c1 = 3c3

Fe: c2=c3

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 c2 = 1 and solve the system of equations for the remaining coefficients:

c1 = 3/2

c2 = 1 c3=1

Multiply by the least common denominator, 2, to eliminate fractional coefficients:

c1 = 3

c2 = 2 c3 = 2

Substitute the coefficients into the chemical reaction to obtain the balanced



Br2 + Fe → Febr3