Step 1: Understand the process of photosynthesis. Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy stored in glucose. The general equation for photosynthesis involves carbon dioxide (CO₂), water (H₂O), and light energy as reactants, and glucose (C₆H₁₂O₆) and oxygen (O₂) as products.
Step 2: Recall the balanced chemical equation for photosynthesis. The correct equation is: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂. This equation shows that six molecules of carbon dioxide and six molecules of water are used to produce one molecule of glucose and six molecules of oxygen.
Step 3: Analyze the given options. Compare each option to the correct photosynthesis equation. Look for the correct arrangement of reactants (CO₂, H₂O, and light energy) and products (C₆H₁₂O₆ and O₂), as well as the proper stoichiometric coefficients (6 for CO₂, H₂O, and O₂).
Step 4: Eliminate incorrect options. For example, the first option incorrectly lists oxygen (O₂) as a reactant instead of a product, and the second option incorrectly lists water (H₂O) as a product instead of a reactant. The fourth option represents cellular respiration, not photosynthesis.
Step 5: Identify the correct answer. The correct equation for photosynthesis is: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂. This matches the third option provided in the problem.