Question

A student dropped few marble pieces in dilute hydrochloric acid in the test tube . the evolved gas was then passed through lime water . what change wolud be observed in lime water? write balancd equations for both the changes observed

Answer 1

(i) Lime water turns milky.
(ii) a) CaCO3 + 2HCl ——> CaCl2 + H2O + CO2
b) CO2 + Ca(OH)2——>CaCO3 + H2O

Answer 2

When dilute HCl is added to marble which is calcium carbonate, it forms calcium chloride, water and carbon dioxide. The chemical equation for the reaction is as follows: CaCO3 + 2HCl → CaCl2 + H2O + CO2

Carbon dioxide gas turns lime water milky due to the formation of calcium carbonate.

The chemical equation showing the reaction between lime water and carbon dioxide is as follows: Ca(OH)2 + CO2 → CaCO3 + H2O