Question

How many molecules are present in 1.6 g of sulphur

Answer 1

>> The molecules formula of sulphur is given to be S8 ( it Contains 8 atoms of sulphur ). So , the molecular mass of sulphur molecule is 32 × 8 = 256 u. This means that 1 mole of sulphur molecules is equal to 256 grams

Answer 2

Given,

mass of Sulphur = 1.6g

Atomic mass of Sulphur = 32g

Number of moles present is given by the expression, Given mass/Atomic mass.

∴ number of moles (n) = 1.6/32

or, n = 0.05 mol.

1 mole contains Avogadro number of molecules.ie,

1 mol = 6. 022x10^23 atoms/molecules

∴ number of moles present in 0.05 mole = 0.05x 6. 022x10^23

or, 3.011x10^22 molecules or atoms.