Question 8:
The chemical formula of Magnesium sulfate (MgSO4) is anhydrous. To find the number of moles of anhydrate in the sample, we need to use the molar mass of anhydrate. The molar mass of MgSO4 is 120.37 g/mol.
4.06 g of MgSO4 / 120.37 g/mol = 0.03367 moles of anhydrate
So, the sample contains 0.03367 moles of anhydrate.