This is the process where fossil fuels, forests, or other carbon-containing substances are burned, adding more carbon dioxide to the air.

The process where fossil fuels, forests, or other carbon-containing substances are burned, addin more carbon dioxide to the air is the combustion.

Some examples of combustion are:

Fossil fuel:

Carbon + O2

C + O2 -> CO2

Forests (wood)

Wood = cellulose = [C6H10O5]n

[C6H10O5]n + 6nO2 = 6n CO2 + 5n H2O

So, in general the combustion of organic matter produces CO2 and water.