The dictionary definiton of light is:
the natural agent that stimulates sight and makes things visible.
I'll paraphrase/give a scientific definition:
Light is made of subatomic particles called photons, which jumps electron shells when they're excited, effecting the electromagnetic spectrum, creating visible light.
Hope this helps. Might not as I'm not perfect on this topic yet.
Answer:
B) Photosynthesis is the process in which light energy is transformed into food energy.
A free-radical substitution reaction is likely to be responsible for the observations. The reaction mechanism of a reaction like this can be grouped into three phases:
- Initiation; the "light" on the mixture deliver sufficient amount of energy such that the halogen molecules undergo homologous fission. It typically takes ultraviolet radiation to initiate fissions of the bonds.
- Propagation; free radicals react with molecules to produce new free radicals and molecules.
- Termination; two free radicals combine and form covalent bonds to produce stable molecules. Note that it is possible for two carbon-containing free-radicals to combine, leading to the production of trace amounts of long carbon chains in the product.
Initiation

where the big black dot indicates unpaired electrons attached to the atom.
Propagation






Termination

Iron rusts when in contact with water.
Answer:
study of chemical used in industries