Madelung constant for NaCl, lattice energy and enthalpy of solution
Needing some help with an inorganic assignment...
2 questions that I have no idea how to do and are not explained in our text (Descriptive Inorganic Chemistry 4ed - Rayner).
1. Calculate the first three terms of the series for the Madelung constant for the sodium chloride lattice. How does this compare with the limiting value? (Apparently none of my classmates are familiar with this either).
2. For an ionic compound, MX, the lattice energy is 1205kJ/mol and the enthalpy of solution is -90kJ/mol. If the enthalpy of hydration of the cation is 1.5 times that of the anion, what are the enthalpies of hydration of the ions?
These have frustrated me for a longer amount of time than I care to volunteer.
Help please -- anything! Thanks. :'(