To make it easier, assume that we have a total of 100 g of a copper acetate hydrate. Hence, we have 31.82g of Cu, 59.14g of acetate and 9.18g of water. Know we will convert each of these masses to moles by using the atomic ie molecular masses of Cu, acetate, and water:
31.82/63.6= 0.5 mole of Cu
59.14/59= 1 mole of acetate
9.18/32= 0.51 mole of water
Now, we will divide all the mole numbers by the smallest among them and get the number of atoms in the compound:
Cu = 0.5/05 = 1
acetate = 1 1/0.5= 2
water = 0.5/051 = 1
So, the empirical formula of the compound Cu(C2H3O2)2 × H2O