Question

What does the passing of carbon dioxide through slaked lime give?

Answer 1

Reaction of slaked lime $\left(\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\right)$ with carbon dioxide:

• “Calcium hydroxide reacts slowly with the carbon dioxide in the air to form a thin layer of calcium carbonate on the walls.”
• When Calcium hydroxide $\left(\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\right)$ reacts with carbon dioxide $\left({\mathrm{CO}}_2\right)$, Calcium carbonate $\left({\mathrm{CaCO}}_3\right)$ is formed along with water $\left({\mathrm{H}}_2\mathrm{O}\right)$.
• The chemical equation can be depicted as:

$\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right)\to {\mathrm{CaCO}}_3\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

Uses of slaked lime:

• In sewage systems, slaked lime is used as a flocculant.
• Slaked lime has wide applications in the food industry.