Question

Name a solution that turns milky on reacting with CO₂.

Answer 1

• Lime water has the chemical formula of $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$ also known as Calcium Hydroxide.
• When Carbon dioxide gas is passed through lime water it turns milky. This reaction works as a test to detect the evolution of Carbon dioxide gas.
• The reaction between limewater and Carbon dioxide -
• $$\begin{gathered} \mathrm{Ca}{\left(\mathrm{OH}\right)}_2+{\mathrm{CO}}_2\to {\mathrm{CaCO}}_3+{\mathrm{H}}_2\mathrm{O} \\ \mathrm{Lime}\mathrm{water}\mathrm{Carbon}\mathrm{dioxide}\mathrm{Calcium}\mathrm{carbonate}\mathrm{Water} \end{gathered}$$
• The formation of insoluble Calcium Carbonate causes the milkiness of the solution