Question

Which is the percent composition of phosphorus in Be3(PO4)2?

a) 4.15 %
b) 28.5%
c) 16.0%
d) 14.6%

Answer 1

Answer : The correct option is (d) 14.6 %

Explanation :

Percent composition : It is calculated by dividing the mass of each element in one mole of the compound that means dividing the mass of each element by the total molar mass of the compound.

Formula used :

`\%\text{ Composition of phosphorus}=\frac{\text{Mass of phosphorus element}}{\text{Molar mass of compound}}* 100`

Molar mass of compound,
`Be_3(PO_4)_2` = 216.9 g/mol

Molar mass of phosphorus = 30.9 g/mol

`\%\text{ Composition of phosphorus}=(31g/mol)/(217g/mol)* 100`

`\%\text{ Composition of phosphorus}=14.6\%`

Therefore, the percent composition of phosphorus in
`Be_3(PO_4)_2` is 14.6 %.