CUET Preparation Today
Assertion: A solution of slaked lime is used for whitewashing walls. Reason: Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls. Choose the correct option out of the following. |
Both assertion and reason are correct, and reason is the correct explanation of assertion. Both assertion and reason are correct, but reason is not the correct explanation of assertion. Assertion is correct but reason is incorrect. Assertion is incorrect but reason is correct. |
Both assertion and reason are correct, and reason is the correct explanation of assertion. |
The correct answer is option 1. Both assertion and reason are correct, and reason is the correct explanation of assertion.
CaO(s) + H2O(l) → Ca(OH)2(aq) + Heat
Quick lime Slaked lime
A solution of slaked lime produced is used for whitewashing walls. Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls. Calcium carbonate is formed after two to three days of whitewashing and gives a shiny finish to the walls. It is interesting to note that the chemical formula for marble is also CaCO3. Ca(OH)2(aq) + CO2(g) → CaCO3(s) + H2O(l) |
