How many glucose molecules are required to balance the following reaction?
\(-C_6H_{12}O_6 +24O_2 \rightarrow 24CO_2+ 24H_2O+Energy \)

For a chemical reaction to be balanced, the amount of reactants must be the same as the amount of products. Counting the number of carbon dioxide molecules on the right we find 24 total. As there are naturally 6 carbons in the glucose molecule on the left, we need 4 groups of these 6 molecules to match the 24 on the right.