What is carbon dioxide?

Structure and properties

Carbon dioxide is a gas that you can’t see or smell at room temperature. It has one carbon atom and two oxygen atoms in each molecule, so its chemical formula is CO2.

This image shows a molecular model of a carbon dioxide molecule, which consists of one carbon atom and two oxygen atoms bonded together. The carbon atom is black, the oxygen atoms are red, and the bonds are white.

CO2 in the atmosphere

Carbon dioxide is a gas that goes in and out of the air. Some things that add carbon dioxide to the air are cars that burn fuel and living things that breathe. Some things that take carbon dioxide from the air are plants that make food and water that dissolves it. Carbon dioxide is a small part of the air, but it is important because it keeps the Earth warm. It does this by trapping heat from the sun.

But too much carbon dioxide can make the Earth too warm. This is called global warming, and it can change the weather in bad ways. For example, it can make some places very dry and some storms very strong. This is why we need to be careful about how much carbon dioxide we put in the air.

Summary:

Carbon dioxide is a compound with one carbon atom and two oxygen atoms in each molecule.
Carbon dioxide is a greenhouse gas that traps heat in the atmosphere.
Carbon dioxide is used to make drinks bubbly and food fresh.