Structure and properties. At room temperature carbon dioxide is a colourless and odourless gas. The carbon dioxide molecule is made up of one carbon atom joined to two oxygen atoms. This means it has a chemical formula is CO₂
Atomic mass of carbon is 12gm. 12 gm of carbon contains 6.02×10^23 no of atoms. If 12 gm of C contains Avogadro's no of atoms then 6gm of C will have half of avogadro's no of atoms(1/2×6.02×10^23) =3.01×10^23 no of atoms