Question

The lattice enthalpy and hydration enthalpy of four compounds are given below
`{:("Compound","Lattice enthalpy","Hydration enthalpy"),(,("in kJ mol"^(-1)),("in kJ mol"^(-1))),(P,+780,-920),(Q,+1012,-812),(R,+828,-878),(S,+632,-600):}`
The pair of compounds which is soluble in water is
A. P and Q
B. Q and R
C. R and S
D. P and R

Answer 1

Correct Answer - D
A compount is soluble in water when its hydration enthalpy is greater than its lattice enthalpy.