Chemistry
Grade-9
Easy
Question
The mass of CaO that can be prepared by heating 200kg of limestone which is 95% pure is:
- 212 kg
- 313 kg
- 112 kg
- 121 kg
Hint:
As 95% purity hence, 190kg reacts.
The correct answer is: 112 kg
CaCO3 
CaO + CO2
1 mole limestone gives 1 mole CaO.
100g limestone gives 56g CaO.
But as 95% purity hence, 190kg reacts.
190kg limestone will give 106.4kg CaO.
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