What's the equation for photosynthesis ?

Carbon dioxide plus water is converted using light energy into sugar and oxygen, or chemically: 6CO2 + 6H2O --light--> C6H12O6 + 6O2 But it's important to realise why the equation is like it is as that will help you understand it better and remember it easier. Photosynthesis is the conversion of one energy source (light) into another (chemical energy), however nothing is 'lost', just converted Sugar, or glucose, consists of 6 carbon atoms and carbon dioxide contains only one carbon atom therefore for each glucose molecule made, you need 6 carbon dioxide molecules to balance it out which is why the equation is 6 CO2 However, glucose also contains 6 oxygen atoms which is why you require 6 molecules of water to produce those atoms in the glucose molecule The more important chemical formula to learn is Glucose = C6H12O6 and once you memorise that, the rest is just balancing the numbers!