Question

The following reaction is balanced, True or False? P4 + 2 O2 → 2 P2O3 True False

Answer 1

The easiest way to tell is by counting up the number of each chemical species on both sides of the equation. We see that as given, there are four phosphorous atoms on both sides, but there are four oxygens on the left and six on the right. This is not balanced.

It should actually be $P_4 + 3O_2$ → $2P_2O_3$.