Balance

the

chemical equation

К+O2=

К2O

4K + O2 = 2K2O

Explanation:

You have to make sure that the same amount of elements are on both sides of the equation. It's a rule in chemistry that you cannot add or take away subscripts in the equation because that changes the compounds, so you sometimes have to play around with the coefficients to make the equation equal. Any coefficient at the beginning of the compounds distribute to each element.