Experimental Measurement of the Lattice Energies of RbBr and NaCl

By measuring electrically the ion emission through an orifice in an equilibrium chamber at high temperature containing salt vapor the lattice energies are calculated. The values obtained are 151.3 kcal. for RbBr and 181.3 kcal. for NaCl. The probable error is about 3.0 kcal. for both measurements, and the maximum error in the neighborhood of 7.5 kcal. The corresponding electron affinities are 84.2 kcal. for Br and 88.3 kcal. for Cl.