If you needed 2.50g of CuSO4 for a reaction but only had CuSO4 * 5H2O available, how many g would you need to use to get the same number of moles of CuSO4?
2.5/molar mass CuSO4 = moles CuSO4.
You need the same moles CuSO4.5H2O.
moles CuSO4.5H2O = mols x molar mass.
To determine how many grams of CuSO4 * 5H2O would be needed to obtain the same number of moles as 2.50g of CuSO4, we can use the molar mass and stoichiometry.
First, we need to find the molar mass of CuSO4 and CuSO4 * 5H2O:
- Molar mass of CuSO4 = atomic mass of Cu (63.55 g/mol) + atomic mass of S (32.07 g/mol) + 4 * atomic mass of O (16 g/mol) = 159.61 g/mol
- Molar mass of CuSO4 * 5H2O = Molar mass of CuSO4 + 5 * [atomic mass of H (1.01 g/mol) + atomic mass of O (16 g/mol)] = 249.68 g/mol
Next, we calculate the number of moles of CuSO4:
- Moles of CuSO4 = Given mass of CuSO4 / Molar mass of CuSO4 = 2.50 g / 159.61 g/mol ≈ 0.0157 mol
Finally, we determine the mass of CuSO4 * 5H2O that corresponds to this amount of moles:
- Mass of CuSO4 * 5H2O = Moles of CuSO4 * Molar mass of CuSO4 * 5H2O = 0.0157 mol * 249.68 g/mol ≈ 3.92 g
Therefore, you would need to use approximately 3.92 grams of CuSO4 * 5H2O to obtain the same number of moles as 2.50 grams of CuSO4.