Question

Why is photosynthesis an example of chemical reaction

Answer 1

The reaction for photosynthesis is 6CO2 + 6H2O --(Light)-->C6H12O6 + 6O2. This process is useful as it enables plants to turn light energy, usually given from the sun, into chemical energy in the form of glucose (C6H12O6) and oxygen (O2), which can be used for the plant's biochemical activities

Answer 2

What Nooreain said, though I would like to add that it is a synthesis reaction ( A+B Yields AB) that, like all chemical reactions, changes/rearranges the molecular or ionic structure of a substance. In simpler terms, a substances is changed into a new substance.