Answer:
CO2 and H2O are the reactant in the given formula.
Step-by-step explanation:
The chemical equation that is mentioned in the question is the reaction of photosynthesis. During photosynthesis process the atmospheric CO2 reacts with H2O or water to generate glucose(C6H12O6) along with the liberation of oxygen gas(O2)
We all know that the substances those are present in the left side of a chemical or biochemical reaction are termed as reactant.
From that point of view it can be stated that in the given reaction CO2 and H2O act as reactant.