Carbon Dioxide Molecular Formula

Chemical or Molecular Formula for Carbon Dioxide

Carbon Dioxide
This is the space-filling molecular structure for carbon dioxide. Ben Mills

Carbon dioxide normally occurs as a colorless gas. In solid form it is called dry ice. The chemical or molecular formula for carbon dioxide is CO2. The central carbon atom is joined to two oxygen atoms by covalent double bonds. The chemical structure is centrosymmetric and linear, so carbon dioxide has no electric dipole.

Key Takeaways: Carbon Dioxide Chemical Formula

  • The chemical formula for carbon dioxide is CO2. Each carbon dioxide molecule contains one carbon atom and two oxygen atoms, bound to each other by covalent bonds.
  • At room temperature and pressure, carbon dioxide is a gas.
  • The carbon dioxide molecule is linear.

Carbon dioxide is soluble in water, where it acts as a diprotic acid, first dissociating to form the bicarbonate ion and then carbonate. A common misconception is that all dissolved carbon dioxide forms carbonic acid. Most dissolved carbon dioxide remains in molecular form.

Why Is Water Bent and Carbon Dioxide Linear?

Both water (H2O) and carbon dioxide (CO2) consist of atoms connected by polar covalent bonds. Yet, water is a polar molecule while carbon dioxide is nonpolar. The polarity of the chemical bonds within a molecule is not sufficient to make the molecule polar. Each water molecule has a bent shape because of the lone electron pair on the oxygen atom. Each C=O bond in carbon dioxide is polar, with the oxygen atom pulling the electrons from carbon toward itself. The charges are equal in magnitude, yet opposite in direction, so the net effect is to produce a nonpolar molecule.