Question

How can I balance this equation? ____ KClO3→ ____ KCl+ ____ O2

Answer 1

the K and Cl are 1:1 .. the problem is in the O .. you have 3 
(left side) and 2 (right side) .. you multiply the O2 on the right by 3 .. 

KClO3 ---> KCl + 3 O2 

and now you have 6 O on the right and 3 on the left .. so you multiply the KClO3 by 2 .. 

2 KClO3 ---> KCl + 3 O2 

now you have 6 O on both sides .. now balance the K and Cl by multiplying KCl on the right by 2 .. 

2 KClO3 ---> 2 KCl + 3 O2