Abstract

In our work two isomorphous salts , CusO4.5H2O - ZnSO4 .7H2O were taken. They were allowed to crystallize after dissolving them in water at various ratios. Then the crystals were analyzed by titrometry technique. Many equations suggested for co-crystallization of salts, in equilibrium and non-equilibrium conditions, were tested. Finally it is found that our system obeys the laws applicable for non-equilibrium condition. Further is also found that in the crystallization of mixed salt , the mixed crystals contain the same number of water of hydration molecules in both salts as the number of molecules salt which in greater amount . for example in our case when the amount of copper sulphate is greater , then the mixed crystal Zinc sulphate also contains 5 water molecules and vice versa. This finding of our work will be very useful in future to prepare a salt with a number of water molecules different from that of its usual number of water molecules.