Compounds and chemical bonding: bringing atoms together

Abstract

This chapter examines compounds and chemical bonding. A compound is a substance that comprises atoms of more than one element. Chemical bonds hold the components of a compound together and are formed by the redistribution of valence electrons between atoms. According to the octet rule, valence electrons are redistributed so that atoms achieve full valence shells that typically contain eight electrons. The chapter then differentiates between the two types of chemical bond: ionic and covalent. An ionic bond forms when one or more electrons are totally transferred from one atom to another to generate an ionic compound. A covalent bond, however, forms when one or more pairs of electrons are shared between atoms to generate a covalent compound. The chapter looks at polarized bonds, in which electrons are shared unequally between two nuclei, and discusses how valency describes the number of chemical bonds an atom of a given element can participate in. It also describes chemical bonding in terms of atomic and molecular orbitals before discussing aromatic compounds and polyatomic ionic compounds.