Question

Samples of gases O₂ , N₂ , CO and CO₂ under the same conditions of temperature and pressure contain the same number of molecules represented by X. The molecules of oxygen occupy V litres and have a mass of 8 g. Under the same conditions of temperature and pressure, what is the volume occupied by : 

1. X molecules of N₂ . 

2. 3X molecules of CO. 

3. What is the mass of CO₂ in grams. 

4. In answering the above questions, whose law has been used. 

(C = 12, N = 14, O = 16)

Answer 1

(i) According to Avogadro's law

Volume of x molecules of N₂ = Volume of X molecules of O₂ = V litres

(Under similar T and P)

(ii) Volume of X molecules of CO = Volume of X molecules of O₂ = V litres

∴ Volume of 3 X molecules of CO = 3 V litres

(Under similar T and P)

(iv) Avogaro's Law has been used in answering the above problems.