Question

What mass of CaO will be obtained by heating 3 mole of CaCO₃ [Atomic mass of Ca = 40] ?  

(A) 150 g 

(B) 168 g 

(C) 16.8 g 

(D) 15 g

Answer 1

168 g mass of CaO will be obtained by heating 3 mole of CaCO₃ [Atomic mass of Ca = 40].

Explanation :-

 3CaCO₂ ⎯→ 3CaO + 3CO₂ 

∴ Molecular mass of CaO is = 40 + 16 = 56 

∵ 3CaO is formed in the reaction. 

∴ 3 × 56 = 168 g of CaO is formed.