Question

Write the balanced equation for the following reaction.

The reaction of carbon dioxide with calcium carbonate.

Answer 1

• Carbon dioxide does not directly react with calcium carbonate instead it reacts with limewater($\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$) to form calcium carbonate (${\mathrm{CaCO}}_3$), which is then precipitated out of the solution. In addition to that, water is also produced. The balanced chemical equation for this reaction is given below;

$\underset{\mathrm{Limewater}}{\mathrm{Ca}{\left(\mathrm{OH}\right)}_2(\mathrm{aq})}+\underset{\mathrm{Dioxide}}{\underset{\mathrm{Carbon}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}}\to \underset{\underset{\mathrm{carbonate}}{\mathrm{Calcium}}}{{\mathrm{CaCO}}_3}\left(\mathrm{s}\right)+\underset{\mathrm{water}}{{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{l}\right)$

• Calcium carbonate precipitates out as solid particles of chalk. This makes the liquid turn ‘white milky’.
• When an excess carbon dioxide is bubbled through the solution for an extended period of time, another acid-base reaction takes place and the solution turns out to be clear and colorless. It happens because of the formation of water-soluble calcium hydrogen carbonate($\mathrm{Ca}{\left({\mathrm{HCO}}_3\right)}_2$).
• The balanced chemical equation for this reaction is given as;

$\underset{\mathrm{Carbonate}}{\underset{\mathrm{Calcium}}{{\mathrm{CaCO}}_3\left(\mathrm{s}\right)}}+\underset{\mathrm{water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\underset{\underset{\left(\mathrm{excess}\right)}{\mathrm{Carbon}\mathrm{dioxide}}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbonate}}{\underset{\mathrm{Calcium}\mathrm{hydrogen}}{\mathrm{Ca}{\left({\mathrm{HCO}}_3\right)}_2\left(\mathrm{aq}\right)}}$