Question

When we blow exhaled air into the solution of lime water, it turns milky. What actually happens in the solution?

Answer 1

When exhaled air is blown through Lime Water which is also known as calcium hydroxide, the carbon dioxide present in the exhaled air reacts with the Lime water and turns it into a milky solution, since the CO2 reacts with Ca(OH)2 and forms CaCO3 or Calcium Carbonate, which is insoluble and white in color.

CaOH2 + CO2 -------> CaCO3 + H2O.