Final answer:
To find the mass of CuSO4 for the given number of formula units, we calculate the molar mass and then use it in a proportion to determine the required mass based on Avogadro's number.
Step-by-step explanation:
The question asks for the mass of CuSO4 when there are 7.8x1025 formula units of the compound. To find the mass, we would first determine the molar mass of CuSO4.
The molar mass is calculated from the molar masses of copper (Cu), sulfur (S), and oxygen (O), which add up to approximately 159.61 g/mol. Since 1 mole of CuSO4 contains 6.022×1023 formula units, we can set up a proportion using the molar mass to determine the mass of 7.8x1025 formula units.
Mass of 7.8x1025 formula units = (7.8x1025 formula units) / (6.022×1023 formula units/mol) × 159.61 g/mol.
After performing the calculation, we will get the desired mass of CuSO4.