The conservation of law states that in a chemical reaction mass is neither created or destroyed therefor the total amount of mass for the reactant for photosynthesis are 6 carbon dioxides 6 waters and sunlight. The mass of each reactant adds to equal up to the mass of the product. Which are going to be 1 glucose and 6 oxygen. Which will then equal the amounts of each atom on both ends of this equation. This can be confusing at some points due to the energy (sunlight) is the reaction in the chemical equation and not the product or outcome. The energy can be converted from one end to another in photosynthesis. Energy is converted form sunlight into sugar or glucose which the body then breaks down for energy.