Final answer:
To find the mass of CuSO₄·5H₂O containing 5.00 moles of H atoms, calculate the moles needed and multiply by the molar mass, resulting in 124.84 grams.
Step-by-step explanation:
The task is to calculate the mass of CuSO₄·5H₂O needed to obtain a sample containing 5.00 mol of hydrogen atoms (H). First, we need to determine the number of moles of CuSO₄·5H₂O required to have 5.00 moles of H atoms. Since there are 5 water molecules in CuSO₄·5H₂O, each with 2 hydrogen atoms, we have 10 hydrogen atoms per molecule of CuSO₄·5H₂O. Therefore, one mole of CuSO₄·5H₂O will contain 10 moles of hydrogen atoms. To find the number of moles of CuSO₄·5H₂O having 5.00 moles of H, we divide the total moles of H needed by 10: 5.00 mol H / 10 = 0.500 mol CuSO₄·5H₂O.
Now, we calculate the molar mass of CuSO₄·5H₂O: (63.55 for Cu) + (32.07 for S) + (4 * 16.00 for O) + (5 *(2 * 1.01 + 16.00 for 5H₂O)) = 249.68 g/mol. Multiply the moles of CuSO₄·5H₂O by its molar mass to find the mass needed: 0.500 mol CuSO₄·5H₂O * 249.68 g/mol = 124.84 g. Therefore, you would need to weigh out 124.84 grams of CuSO₄·5H₂O to get a sample containing 5.00 moles of hydrogen atoms.