Final answer:
The coefficients of a balanced reaction indicate how much of each reactant will be used up in a reaction.
Step-by-step explanation:
The correct answer is B. The coefficients of a balanced reaction.
In a balanced chemical equation, the coefficients show the mole ratio between the reactants and products. The coefficients represent the number of moles of each reactant that are required for the reaction to proceed. By comparing the coefficients of the reactants, you can determine how much of each reactant will be used up in the reaction.
For example, in the balanced equation:
2H2 + O2 → 2H2O
The coefficient of H2 is 2, which means that 2 moles of H2 are required for every 1 mole of O2. This indicates that twice as much H2 will be used up compared to O2 in the reaction.