A 1.547-g sample of blue copper(II) sulfate pentahydrate, CuSO45H2O, is heated carefully to drive off the water.

Question:

A 1.547-g sample of blue copper(II) sulfate pentahydrate, CuSO4∙5H2O, is heated carefully to drive off the water. The white crystals of CuSO4 that are left behind have a mass of 0.989 g. How many moles of H2O were in the original sample? Show that the relative molar amounts of CuSO4 and H2O agree with the formula of the hydrate.