Quick Lime is a
- ACarbonate of lime
- BOxide of calcium
- CProduct left immediately after the calcination of pure limestoneCorrect
- DLime quickly treated with water
Solution
Concept
Chemical composition of quick lime
Formula
NONE
Step-by-step solution
1. Quick lime (calcium oxide, CaO) is produced by heating limestone (calcium carbonate, CaCO3) in a process called calcination. 2. The calcination process drives off carbon dioxide gas, leaving behind calcium oxide. 3. Thus, quick lime is the product left immediately after the calcination of pure limestone. Answer: C
Explanation
Quick lime is chemical calcium oxide produced by heating pure limestone or calcium carbonate to high temperatures. This heating process, known as calcination, expels carbon dioxide gas from the stone. The dry material left immediately after calcination is quick lime.
Why the other options are wrong
A) Carbonate of lime refers to unburnt limestone (calcium carbonate). B) Calcium oxide is the chemical composition of quicklime, but option C provides its definition as the immediate product left after calcination. D) Lime treated with water is slaked lime or hydrated lime.
Shortcut
Quick Lime = Calcium Oxide (CaO).
Common mistake
Selecting option D due to the word "quickly" instead of recognizing quicklime as the immediate calcination product of limestone.
Correct answer: C) Product left immediately after the calcination of pure limestone