To help compare sizes of different surface areas, we list here areas of the order of 1018 square metres, i.e. those between 1 trillion km2 and 10 trillion km2. See alsoareas of other orders of magnitude.
... the light that is not absorbed by the pigment molecules.
The typical overall chemical reaction of photosynthesis is:
6H2O + 6CO2 + light → C6H12O6 (glucose) + ...