Calculate the no. of moles of phosphorus in 92.9 g phosphorusm assuming that molecular formula of phosphorus is `P_(4)`. Also calculate the no. of atoms and molecules of phosphorus in the sample.

Explanation

(i) No. of moles of phosphorus `(P_(4))`
Molar of phosphorus `(P_(4))=4xx31 = 124 g`
Mass of phosphorus `(P_(4))=92.9 g`
`:.` No. of moles of `P_(4)=("Mass of "P_(4))/("Molar mass of" P_(4))=((92.9g))/((124"g mol"^(-1)))=0.75` mol
(ii) No. of molecules of phosphorous `(P_(4))`
1 mole of `P_(4)` contains molecules `= 6.022 xx 10^(23)`
0.75 mole of `P_(4)` contains molecule `= 6.022 xx 10^(23)xx0.75xx0.75=4,52xx10^(23)` molecules
(iii) No. of atoms of phosphorus
1 molecule of `P_(4)` contains atoms = 4
`:. 4.52 xx 10^(23)` molecules of `P_(4)` contain atoms `= 4 xx 4.52 xx 10^(23) =1.8 xx 10^(24)` atoms.