Final answer:
To find the number of equivalents of PO₄³⁻ in the solution, we need to determine the number of moles of PO₄³⁻ and then convert it to equivalents using Avogadro's number.
Step-by-step explanation:
To find the number of equivalents of PO₄³⁻ in the solution, we need to determine the number of moles of PO₄³⁻ and then convert it to equivalents. Given that the solution contains 4.50 mol of PO₄³⁻, we can use Avogadro's number to convert moles to molecules. One mole of any substance contains 6.02 x 10²³ molecules. So, 4.50 mol of PO₄³⁻ contains 4.50 x 6.02 x 10²³ molecules of PO₄³⁻.
Now, since one equivalent is equal to the amount of a substance that can react with or is equivalent to one mole of hydrogen ions (H⁺), we can divide the number of molecules of PO₄³⁻ by Avogadro's number to find the number of equivalents.
Therefore, the number of equivalents of PO₄³⁻ in the solution is 4.50 x 6.02 x 10²³ / 6.02 x 10²³ = 4.50 equivalents.