C+O2→CO2
CO2 is a green house gas, which act as blanket in earth atmosphere, and cause Green house effect.
Green House Effect:
The Earth gets energy from the sun in the form of sunlight. The Earth's
surface absorbs some of this energy and heats up. That's why the surface
of a road can feel hot even after the sun has gone down—because it has
absorbed a lot of energy from the sun. The Earth cools down by giving
off a different form of energy, called infrared radiation. But before
all this radiation can escape to outer space, greenhouse gases in the
atmosphere absorb some of it, which makes the atmosphere warmer. As the
atmosphere gets warmer, it makes the Earth's surface warmer, too.