Question: how many total oxygen atoms are there in the reactants of photosynthesis?
Answer: When viewed as a whole, the photosynthetic process utilizes 12 water molecules, six carbon dioxide molecules and light energy to produce one glucose molecule, six water molecules and six oxygen molecules. This can be represented by the following chemical equation: 12H20 + 6CO2 + light energy = C6H12O6 + 6H2O + 6O2.