What is the mass percent of phosphorus in Zn3(PO4)2?

• A. 12.8%
• B. 17.9%
• C. 23.7%
• D. 28.2%

Answer: (B)

Verified step by step guidance

1. Identify the chemical formula of the compound: Zn\_3(PO\_4)\_2. This means the compound contains 3 zinc (Zn) atoms, 2 phosphate (PO\_4) groups, and within each phosphate group, 1 phosphorus (P) atom and 4 oxygen (O) atoms.
2. Calculate the molar mass of each element involved: Zn, P, and O. Use the periodic table to find their atomic masses (in g/mol).
3. Calculate the molar mass of the entire compound Zn\_3(PO\_4)\_2 by summing the contributions of all atoms: 3 times the atomic mass of Zn, plus 2 times the molar mass of the PO\_4 group. The molar mass of PO\_4 is the atomic mass of P plus 4 times the atomic mass of O.
4. Calculate the total mass of phosphorus in one mole of Zn\_3(PO\_4)\_2. Since there are 2 phosphorus atoms (one in each PO\_4 group), multiply the atomic mass of P by 2.
5. Find the mass percent of phosphorus by dividing the total mass of phosphorus by the molar mass of Zn\_3(PO\_4)\_2 and then multiplying by 100%: \n\(\text{Mass \% P} = \frac{2 \times M_{P}}{M_{Zn_3(PO_4)_2}} \times 100\%\)