write the reaction for the dehydration of CuSO4 . XH20?

CuSO4.5H2O ==> CuSO4 + 5H2O

Why is it 5 H2O?

You had X. The USUAL amount of water of crystallization in CuSO4 is 5 mols H2O so I used that number. If you rather I had used X, then

CuSO4.XH2O ==> CuSO4 + XH2O

The reaction equation for the dehydration of CuSO4 . XH2O can be determined by considering the loss of water molecules from CuSO4 . XH2O. To find the appropriate number of water molecules lost, we need to refer to the value of 'X' in CuSO4 . XH2O, which represents the number of water molecules present.

Let's assume that the value of 'X' is 'n' in CuSO4 . XH2O.

The chemical formula for copper(II) sulfate is CuSO4. The dot before X indicates the presence of water molecules, and the subscript 'n' indicates the number of water molecules present.

Therefore, the hydrated copper(II) sulfate compound is CuSO4 . nH2O.

During the dehydration process, the water molecules are eliminated from CuSO4 . nH2O, resulting in the formation of an anhydrous copper(II) sulfate compound.

The reaction equation for the dehydration of CuSO4 . XH2O can be written as:

CuSO4 . nH2O -> CuSO4 + nH2O

This equation indicates that n number of water molecules are removed from CuSO4 . nH2O to form anhydrous CuSO4.

Note: The specific value of 'n' needs to be known to provide the balanced chemical equation for the reaction.