A.) already balanced, double replacement
B.) already balanced, synthesis
C.) 2,1,2,1 - single replacement
D.) 2,1,1,1 - decomposition
E.) 1,2,1,1 - single replacement
F.) 1,1,1,2 - double replacement
G.) 1,5,3,4 - combustion
H.) 2,3,2,3 - single replacement