Final answer:
The mole fractions of H₃PO₄ in a solution of 14.5 g of H₃PO₄ in 125 g of water is 0.02087 and the mole fractions of water is 0.97913.
Step-by-step explanation:
To calculate the mole fractions of H₃PO₄ and water in the solution, follow these steps:
- Calculate the number of moles of H₃PO₄ using its molar mass.
- Calculate the number of moles of water (H₂O) using its molar mass.
- Add the moles of H₃PO₄ and water to find the total number of moles in the solution.
- Divide the moles of H₃PO₄ by the total moles to find the mole fraction of H₃PO₄.
- Divide the moles of water by the total moles to find the mole fraction of water.
Using the molar mass of H₃PO₄ (98.00 g/mol), the number of moles of H₃PO₄ is calculated:
(14.5 g) / (98.00 g/mol) = 0.14796 moles of H₃PO₄
Using the molar mass of water (18.015 g/mol), the number of moles of water is calculated:
(125 g) / (18.015 g/mol) = 6.9402 moles of H₂O
The total number of moles in the solution is:
0.14796 moles of H₃PO₄ + 6.9402 moles of H₂O = 7.08816 moles
The mole fraction of H₃PO₄ is therefore:
(0.14796 moles) / (7.08816 moles) = 0.02087
The mole fraction of water is thus:
(6.9402 moles) / (7.08816 moles) = 0.97913
Note that the sum of the mole fractions will equal 1.