CH 101 Lecture Notes - Lecture 4: Ionic Bonding, Ionic Compound, Electron Affinity
Document Summary
Define oxidation states and show how they are determined in ions and molecules. Explain how to predict the formulas of binary ionic compounds. Ionic bonding : complete transfer of one electron to form a cation, to another atom that forms an anion. Covalent bonding : equal sharing between non metals with identical electron affinities. A metal atom can transfer an electron to a nonmetal. The resulting cation and anion are attracted to each other by electrostatic forces. Much of chemistry involves the transfer of electrons between species. To form nacl, the neutral sodium atom, na, must lose an electron to become a cation : na+ (recall na;s ionization energy) The electron cannot be lost entirely, so it is transferred to a chlorine atom, cl, which then becomes an anion: cl- (recall cl"s electron affinity) The na+ and cl- ions are attracted to form an ionic nacl lattice which crystallizes (coulomb"s law)
