Why the standard enthalpy change of hydration of copper sulphate cannot be measured directly ?

It is difficult to measure the enthalpy change of hydration accurately in a direct way because the hydration process can't be controlled directly. Instead, anhydrous and hydrated copper(II) sulfate can be dissolved in water. Each 'route' produces a solution of hydrated copper(II) sulfate.

they include patterns; cause and effect; scale, proportion, and quantity; systems and system models; energy and matter; structure and function; and stability and change.

can i get the brainiest answer

i answered it first