Fe3+ and Cu2+ can be separated by using excess of NH3(aq), as follows:
Excess ofNH3(aq) percipitates Fe3+ as Fe(OH)3
while Cu2+ remains soluble as [Cu(NH3)4]2+,
White ppt. with Bacl2⇒SO2−4,
Choclate coloured ppt with K4[Fe(CN)6]⇒Cu2+,
Thus, hydrated salts is : CuSO4⋅xH2O
CuSO4⋅xH2O⟶BaSO4
159.5+18x 233
2.495 2.33
∴x=5