How do I balance this equation? ?KNO3 → ?K2O + ?N2(g)+ ?O2(g) and what type of reaction is it?

4KNO3 ==> 2K2O + 2N2 + 5O2

Explanation:

It's a decomposition, but not a simple one.

KNO3 ==> K2O + N2 + O2   I don't usually do this, but I think the easiest way to proceed is to  balancing the K and N together. That will require a 2 in front of KNO3

4KNO3 ==> 2K2O + 2N2 + 5O2

Now you have (3*4) = 12 oxygens. Two are on the K2O. So the other 10 must be on the O2

That should do it.

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