Question

When lithium iodide (LiI) is dissolved in water, the solution becomes hotter.

      [ Hint: According to Hess’s Law, the overall enthalpy change upon solution formation is

      the sum of the changes in enthalpy for each step. Recall which two terms on the right

      hand side of the equation below combine to make the heat of hydration. ]

       H_solution = H_solute + H_solvent + H_mixing

a.)   Is the dissolution of LiI endothermic or exothermic?

   •   What can you conclude about the relative magnitudes of the lattice energy of

LiI and its heat of hydration?

   •   Why does the solution form (i.e. what drives the process)?