Question

How many molecules of H2SO4 will have same mass of oxygen present in 4.4g of CO2.

(At. mass of H2SO4 = 98, CO2 = 44, C = 12, O = 16)​

Answer 1

To Find₁ : The mass of oxygen present in 4.4 g of CO₂.

As, 1 molecule of CO₂ contains 2 O-Atoms

So, 1 mol CO₂ ≡ 2 mol O-atoms

Or 44 g of CO₂ ≡ 32 g of O-atoms

On dividing both sides by 10;

4.4 g of CO₂ ≡ 3.2 g of O-atoms (1)

0.1 mol CO₂ ≡ 0.2 mol O-atoms

or 4.4 g CO₂ ≡ 1.6 g O₂ molecules

To Find₂: Number of molecules of H₂SO₄ containing same mass of Oxygen

As, 1 moleule of H₂SO₄ contains 4 oxygen atoms

So, 1 mol H₂SO₄ ≡ 4 mol O-atoms

Or 98 g H₂SO₄ ≡ 64 g O-atoms

On dividing both sides by 20;

4.9 g of H₂SO₄ ≡ 3.2 g of O-atoms (2)

or 4.9 g H₂SO₄ ≡ 1.6 g of O₂ molecules

***From (1) & (2);

4.9 grams of Sulphuric acid will contain the same mass of Oxygen as in 4.4g of CO₂