Answer:
[tex]\boxed{5.90 \times 10^{24}}[/tex]
Explanation:
Step 1. Calculate the formula units of Cu₃(PO₄)₂
[tex]\text{4.90 mol Cu$_{3}$(PO$_{4}$)$_{2}$} \times \dfrac{6.022 \times 10^{23} \text{ formula units}}{\text{1 mol Cu$_{3}$(PO$_{4}$)$_{2}$}}\\\\=\text{2.951 $\times$ 10$^{24}$ formula units Cu$_{3}$(PO$_{4}$)$_{2}$}[/tex]
Step 2. Calculate the atoms of P
[tex]\text{Atoms of P}\\\\=\text{2.951 $\times$ 10$^{24}$ formula units Cu$_{3}$(PO$_{4}$)$_{2}$} \times \dfrac{ \text{2 atoms P}}{\text{1 formula unit Cu$_{3}$(PO$_{4}$)$_{2}$}}\\\\= \boxed{5.90 \times 10^{24} \text{ atoms P}}[/tex]
