Question

The pair of gases containing the same number of molecules is

(a) 22 g of CO₂ and 72 g of N₂

(b) 11 g of CO₂ and 28 g of N₂

(c) 44 g of CO₂ and 7 g of N₂

(d) 11 g of CO₂ and 7g of N₂

Answer 1

Correct option is (d) 11 g of CO₂ and 7g of N₂

11 g of CO₂ = 11/44 = 0.25 moles

7 g of N₂ = 7/28 = 0.25 moles 

(Hence, same number of molecules in the two gases).