If 1 gram of sulphur dioxide contains x molecules, how many molecules will be present in 1 gram of oxygen?(S = 32 u ; O = 16 u)

Mass of sulphur dioxide = 1g (given)

We know that equal moles of all substances contain an equal number of molecules.

(1 mole of all substances contains 6.022 × 10²³ molecules).

Therefore, the ratio of molecules in sulphur dioxide and oxygen will be the same as the ratio of their moles.

Number of moles in 1g of sulphur dioxide:

1 mole of SO₂ = (1 × 32) + (2 × 16) = 64g

64g of SO₂ = 1 mole of SO₂

Therefore, 1g of SO₂ = 1/64 moles of SO₂

Now, 1/64 moles of SO₂ contain x molecules (given).

Since an equal number of molecules are present in equal moles of all substances, 1/64 moles of oxygen will also contain x number of molecules.

Number of moles in 1g of oxygen:

1 mole of O₂ = 2 × 16 = 32g

32g of O₂ = 1 mole of O₂

Therefore, 1g of O₂ = 1/32 moles of O₂

We have already stated that 1/64 moles of oxygen contain x molecules.

Therefore, 1/32 mole of oxygen will contain = x × 64 / 32 = 2x

Hence, 1 gm of oxygen consists of a 2x number of molecules.