Question

What will be the volume of CO₂ at NTP obtained on heating 10 grams of (90% pure) limestone? 

(A) 22.4 litre 

(B) 2.016 litre 

(C) 2.24 litre 

(D) 20.16 litre

Answer 1

Correct option: (B) 2.016 litre

(10g) CaCO₃ → CaO + CO₂

10 g of 90% pure CaCO₃ ≡ 9 gm of CaCO₃

∴ Number of moles of CaCO₃

∴ Number of moles of CaCO₃ = \(\cfrac{9}{100}\) 

= 0.09 mole

CaCO₃ ≡ CO₂ = 0.09 mole

At NTP Vol. CO₂ = 0.09 x 22.4

= 2.016 L.