An Ionic Bond
(a) Calculate the electric potential energy for a K+ ion and a Br– ion separated by a distance of 0.29nm, the equilibrium separation in the KBr molecule. Treat the ions as point charges.
(b) The ionization energy of the potassium atom is 4.3eV. Atomic bromine has an electron affinity of 3.5eV. Use these data and the results of part (a) to estimate the binding energy of the KBr molecule. Do you expect the actual binding energy to be higher or lower than your estimate? Explain your reasoning.