Calculate the solubility in mol dm-3 of 40g of CuSO4 dissolved in 100g of water at 120oC. [Cu = 64, S = 32, O = 16]

Answer Details

The solubility of a substance is defined as the amount of that substance that can dissolve in a given amount of solvent at a specific temperature and pressure. In this case, we are given 40g of CuSO4 and 100g of water at 120°C, and we need to calculate the solubility of CuSO4 in mol dm-3. To solve this problem, we first need to calculate the molar mass of CuSO4. The molar mass of CuSO4 can be calculated by adding the molar masses of copper (Cu), sulfur (S), and four oxygen (O) atoms in CuSO4. The molar mass of CuSO4 = (64 g/mol for Cu) + (32 g/mol for S) + (4 × 16 g/mol for O) = 64 + 32 + 64 = 160 g/mol Next, we need to calculate the number of moles of CuSO4 that are present in 40g of the compound. This can be done by dividing the mass of CuSO4 by its molar mass. Number of moles of CuSO4 = 40g / 160 g/mol = 0.25 moles Finally, we need to calculate the solubility of CuSO4 in mol dm-3. The solubility is given by the number of moles of the solute (CuSO4) per unit volume of the solution (water). We are given 100g of water, but we need to convert this to dm3. Since the density of water is 1 g/cm3 or 1 g/mL, we can use the fact that 1 dm3 is equal to 1000 mL. Volume of water = 100g / 1 g/mL = 100 mL = 0.1 dm3 Therefore, the solubility of CuSO4 in mol dm-3 is given by: Solubility = Number of moles of CuSO4 / Volume of water in dm3 = 0.25 moles / 0.1 dm3 = 2.5 mol dm-3 So, the correct answer is 2.50 mol dm-3.