CHM 11500 Lecture Notes - Lecture 14: Electric Potential Energy, Lithium Fluoride, Lattice Energy

• School: Purdue University
• Department: Chemistry
• Course: CHM 11500
• Professor: Chittaranjan Das

Document Summary

Chm 115 - lecture 14 - bonding continued. Electron transfer is an endothermic process, meaning it requires input energy to proceed. Ionic compounds still form spontaneously, despite the fact that electron transfer is endothermic. Ionic compounds are stabilized by their lattice energy. Lattice energy = the energy released when ions in the gas phase attract and combine to form a solid crystal. There are generally three steps in the formation of ionic compounds. The conversion of the reactant metal and nonmetal into gaseous atoms (endothermic) The electron transfer from the metallic atoms to the nonmetallic atoms (endothermic) The attraction of ions and crystallization into an ionic solid (exothermic) The third step is what constitutes the lattice energy, it is exothermic enough to overcome the other endothermic steps and allows the formation of ionic compounds to be a spontaneous process. Lattice energy is proportional to the electrostatic potential between two ions. Lattice energy is affected by two factors.