Question

What happens when ${\mathrm{CO}}_2$ is passed through lime water for short duration?

Answer 1

Lime water

• A saturated aqueous solution of calcium hydroxide $\left(\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\right)$ is known as lime water.

Passage of Carbon dioxide gas through lime water

• The formation of calcium carbonate $\left({\mathrm{CaCO}}_3\right)$ occurs when carbon dioxide $\left({\mathrm{CO}}_2\right)$ gas is passed through lime water for a short time.
• Lime water turns milky due to the formation of calcium carbonate.
• The reaction is as follows:

$\underset{\left(\mathrm{Carbon}\mathrm{dioxide}\right)}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}+\underset{\left(\mathrm{Calcium}\mathrm{hydroxide}\right)}{\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)}\to \underset{\left(\mathrm{Calcium}\mathrm{carbonate}\right)}{{\mathrm{CaCO}}_3\downarrow }+\underset{\left(\mathrm{Water}\right)}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$