When the equation KClO 3 ( s ) → KCl( s ) + O 2 ( g ) is balanced, the coefficient of KClO 3 is .
4
2
3
1

Explanation:

Often, the best way to start is to balance all atoms other than O and H, then balance O, then balance H.

1. Put a 1 in front of the most complicated-looking formula (KClO₃):

1KClO₃ ⟶ 2KCl + O₂

2. Balance K:

We have fixed 1 K on the left. We need 1 K on the right. Put a 1 in front of KCl.

1KClO₃ ⟶ 1KCl + O₂

3. Balance Cl:

Done.

4. Balance O:

We have fixed 3 O on the left. We need 3O on the right. Uh, oh. Fractions.

Double every underlined coefficient

2KClO₃ ⟶ 3KCl + O₂

Now, we have 6 O on the left. we can put a 3 in front of O₂.

2KClO₃ ⟶ 3KCl + 3O₂

Every formula now has a coefficient. The equation should be balanced.

5. Check that atoms balance:

The equation  is now balanced.

i just learnt this recently but i need to look through my notes again

the answer is 0.8m.

by: nicholas