Question

What is the percent composition of zinc phosphate (Zn3(PO4)2)? Find the percentage for each element.

Answer 1

Percentage of zinc = 50.81%

Percentage of Phosphorous = 16.05%

Percentage of oxygen = 33.14%

Explanations:

The molecular formula of zinc phosphate is given as:

`Zn_3\mleft(PO_4\mright)_2`

To get the percentage of each element in the compound, we will apply the formula:

`\%\text{composition = }\frac{molar\text{ mass of the element}}{molar\text{ mass of the compound}}*100`

Get the molar mass of the compound.

Given the molar masses of the elements

Zinc = 65.38g/mol

Phosphorous = 30.97g/mol

Oxygen = 15.99g/mol

`\begin{gathered} \text{Molar mass of }\mleft(Zn_3\mleft(PO_4\mright)_2\mright)=3(65.38)+2(30.97)+8(15.99) \\ \text{Molar mass of }(Zn_3(PO_4)_2)=196.14+61.94+127.92 \\ \text{Molar mass of }(Zn_3(PO_4)_2)=386\text{g/mol} \end{gathered}`

Get the percentage composition by mass of each element:

For Zinc element;

`\begin{gathered} \%\text{ of Zn = }(196.14)/(386)*100 \\ \%\text{ of Zn }=50.81\% \end{gathered}`

For Phosphorous element

`\begin{gathered} \%\text{ of Phosphorous = }(61.94)/(386)*100 \\ \%\text{ of Phosphorous = }16.05\% \end{gathered}`

For the oxygen element;

`\begin{gathered} \%\text{ of Oxygen = }(127.92)/(386)*100 \\ \%\text{ of Oxygen }=\text{ }33.14\% \end{gathered}`

Therefore the percentage composition of Zinc, Phosphorous, and Oxygen in zinc phosphate is 50.81%, 16.05%, and 33.14% respectively