The chemical equation shown represents photosynthesis. a plus water plus light with a right-pointing arrow towards b plus oxygen. the arrow has an x above it. what is the role of substance a in photosynthesis? it traps light energy from the atmosphere. it combines with water to form glucose. it cools the atmosphere by changing into vapor. it changes into hydrogen in the presence of light.

Answer;

It combines with water to form glucose.

Explanation;Photosynthesis is a process by which green plants make their own food by using solar energy from the sun, together with water and carbon dioxide.Carbon dioxide, water and light are all needed for photosynthesis to take place. During the process solar energy from the sun is used to convert carbon dioxide and water into the simple sugar glucose. Substance A is the above question represent carbon dioxide which combines with water in presence of light to form simple sugars and oxygen gas.The equation for the reaction is;

6CO2 + 6H2O + light energy = C6H12O6 + 6O2.

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