Question

The enthalpies of solution of anhydrous $Cu{SO}_4$ and $Cu{SO}_4.5H_{2}O$ are $-15.89$ and $2.80$ $kcal/mol$ respectively. The enthalpy of hydration of $Cu{SO}_4$ to $Cu{SO}_4.5H_{2}O$ is:

• A. $-18.69kcal$
• B. $+13.09kcal$
• C. $-13.09kcal$
• D. $+18.69kcal$

Answer 1

The correct option is B $+13.09kcal$

Add both reactions and will get the enthalpy of hydration of $CuS{O}_4\to CuS{O}_4.5H_{2}O$

So $-15.89+2.8=-13.09$