Final answer:
The number of moles of water in 249.6g of hydrated copper sulfate (CuSO4·5H2O) is 5.00 moles, obtained by first determining the molar mass of the compound and then using the calculated moles of the compound to find the moles of water since there are five moles of H2O per mole of the hydrated compound.
Step-by-step explanation:
To calculate the number of moles of water (H2O) in 249.6 g of hydrated copper sulfate (CuSO4·5H2O), one must first determine the molar mass of the compound. The molar mass is calculated by adding together the masses of each element in the compound, taking into account the five molecules of water present per formula unit. The molar mass of CuSO4 is 159.61 g/mol, and the molar mass of 5H2O is (5 × 18.02) 90.10 g/mol. The total molar mass of CuSO4·5H2O is then 249.71 g/mol.
The next step is to convert the mass of the hydrated compound to moles by dividing by the molar mass:
Moles of CuSO4·5H2O = 249.6 g / 249.71 g/mol ≈ 1.00 mol.
Since each mole of CuSO4·5H2O contains 5 moles of H2O, we multiply the moles of the compound by 5 to find the moles of water:
Moles of H2O = 1.00 mol × 5 = 5.00 moles.
Therefore, the correct answer is (D) 5.00 moles of water in 249.6g of hydrated copper sulfate.