What is the chemical equation for enthalpy of solution of hydrated salts? [closed]








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If I take the anhydrous salt $\ce {CuSO\_4}$, the equation for its dissolution in water would be:
$$ \ce {CuSO\_4}\_{(s)} + \ce {aq}.\rightarrow \ce {CuSO\_4}\_{(aq)} $$


Now for the hydrated salt $\ce {{CuSO\_4}\cdot {5H\_2O}}\_{(s)}$, is it this:
$$ \ce {{CuSO\_4}\cdot {5H\_2O}}\_{(s)} + \ce {aq}.\rightarrow \ce {CuSO\_4}\_{(aq)} $$


or is the output the "aqueous version" of the hydrated salt ($\ce {{CuSO\_4}\cdot {5H\_2O}}\_{(aq)}$), if that's even a thing? I think it's the first one, but I don't understand why the salt would become anhydrous when dissolved.




$\ce{CuSO4(aq)}$ is just a shortcut for $\ce{Cu^2+(aq) + SO4^2-(aq)}$.


$$\ce{CuSO4(s) ->[H2O]Cu^2+(aq) + SO4^2-(aq)}$$


$$\ce{CuSO4 . 5 H2O(s) ->[H2O]Cu^2+(aq) + SO4^2-(aq)}$$


As the symbol (aq) means implicitly involved, indefinite amount of ion-hydrating water, the reactions do not need to be enumerated wrt the water molecule count.


Crystal water abandons ions and becomes ordinary water, possibly but not necessarily taking first dibs in ion hydration.


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