We start with
1KClO3→KCl+O2
Balance K :
We have 1 K on the left, so we need 1 K on the right. We put a 1 in front of the KCl .
1KClO3→1KCl+O2
Balance Cl :
Cl is already balanced, with 1 Cl on each side.
Balance O :
We have 3 O atoms on the left and only 2 on the right. We need 1½ O2 molecules on the right. Uh, oh! Fractions!
We start over with a 2 as the coefficient.
2KClO3→2KCl+O2
Now we have 6 O atoms on the left. To get 6 O atoms on the right, we put a 3 in front of the O2 .
2KClO3→2KCl+3O2
Every formula now has a fixed coefficient. We now should have a balanced equation.
