= Carbon dioxide
{title2=$\mathrm{CO}_2$}
{wiki}
= CO2
{c}
{synonym}
<Carbon dioxide> is $\mathrm{CO_2}$, a linear molecule with two carbon-oxygen double bonds. The individual bonds are polar, but their dipoles cancel in the symmetric equilibrium geometry. Some vibrations change the molecular dipole and therefore absorb <infrared> radiation.
Carbon dioxide is a product of many oxidation and combustion processes and a substrate for photosynthetic carbon fixation. Dissolved carbon dioxide participates in carbonate acid-base equilibria, so adding it to water can change <pH> without directly adding a strong acid.
Back to article page
