Question

calculate the number of molecules of phosphorus P4 is present in 124 gram of phosphorus​

Answer 1

Mass of 1 mole of phosphorus(P4) = 124g

So 124 g of phosphorus contains 6x10²³ molecules

P4 molecule contains 4 atoms

So 124g of phosphorus contains =4x 6 x 10²³ atoms

So 12.4g of phosphorus contains = 4 x 6 x 10²³ x 12.4 = 2.4x1023 atoms

124

Mass of 1 mole of phosphorus = 124g

So moles in 12.4g phosphorus = 124 = 10 moles

12.4

Answer 2

No. if mole of P4 molecule = Given wt/Molar wt

= 124/124 = 1 mole .

Hence,

No. of P4 molecules = mole × Avogadro constant

= 1 × 6.023 × 10²³ = 6.023 × 10²³

No. of P atoms in P4 = 4 × mole of P4 × Avogadro constant

= 4 × 1 × 6.023 × 10²³

= 24.092 × 10²³

= 2.4092 × 10²⁴.

Hope it will be helpful.⚔️