Chapter 9

a mixture with metallic properties that consists of solid phases of two or more pure elements, a solid-solid solution, or distinct intermediate phases

the standard enthalpy change (always > 0) accompanying the breakage of a given bond in 1 mol of gaseous molecules

the distance between the nuclei of two bonded atoms

the number of electron pairs shared by two bonded atoms

a series of hypothetical steps and their enthalpy changes that converts elements to an ionic compound; it is used to calculate the lattice energy

a law stating that the electrostatic energy between particles A and B is directly proportional to the product of their charges and inversely proportional to the distance between them

a type of bond in which atoms are bonded through the sharing of electrons; the mutual attraction of the nuclei and an electron pair that holds atoms together in a molecule

the idealized bonding type that is based on localized electron-pair sharing between two atoms with little difference in their tendencies to lose or gain electrons (most commonly nonmetals)

a covalent bond that consists of two bonding pairs; two atoms sharing four electrons in the form of one σ and one π bond

the relative ability of a bonded atom to attract shared electrons

the difference in electronegativities between two bonded atoms

a qualitative description of metallic bonding proposing that metal atoms pool their valence electrons in a delocalized “sea” of electrons in which the metal ions (nuclei and core electrons) are submerged in an orderly array

an instrumental technique for determining the types of bonds in a covalent molecule by measuring the absorption of IR radiation

a gaseous ionic molecule, formed when an ionic compound vaporizes

the idealized type of bonding based on the attraction of oppositely charged ions that arise through electron transfer between atoms with large differences in their tendencies to lose or gain electrons (typically metals and nonmetals)

the enthalpy change (always positive) that accompanies the separation of 1 mol of a solid ionic compound into gaseous ions

a notation in which the element symbol represents the nucleus and inner electrons and surrounding dots represent the valence electrons

an electron pair that is part of an atom’s valence level but not involved in covalent bonding

an idealized type of bonding based on the attraction between metal ions and their delocalized valence electrons

a covalent bond between identical atoms in which the bonding pair is shared equally

the observation that, when atoms bond, they often lose, gain, or share electrons to attain a filled outer level of eight electrons

an estimate of the actual charge separation in a bond (caused by the electronegativity difference of the bonded atoms) relative to complete separation

a covalent bond in which the electron pair is shared unequally, so the bond has partially negative and partially positive poles

a bond that consists of one electron pair