NaCl has a lattice energy of -787 kJ/mol. Consider a hypothetical salt XY. X3+ has the same radius of Na+ and Y3- has the same radius as Cl-. Estimate the lattice energy of XY.

Solution 94E Step 1 of 2 Lattice Energy depends on ionic radii (there’s a reverse proportionality) and ion’s charge (there exists a direct proportionality). The dependence on ion’s charge can be expressed by the coulombic equation states that the magnitude of potential energy of two interacting charges is given by: Here, are charges on particles that compose atoms r, distance between the charges