Chapter 6 Study Guide: Bonding

Review Electronegativity Trends, Electron Configurations, Valence Electrons, Lewis Electron Dots.

Cations: stable metals, lose electrons, positive charge, smaller than their neutral atom. Anions: stable nonmetals, gain electrons, negative charge, larger than their neutral atom. Goal is to obtain eight valence electrons to be stable like the noble gases. Ionic Compounds: formula units made out of a cation and an anion (+)(-) = 0 Ionic Bonds: the cation transfers electrons completely to the anion. * no lines, no shapes, no polarity, no interMOLECULAR attractions Properties: crystalline solids, high melting and boiling points, good conductors of electricity if molten or aqueous with free moving ions. Ionic Character: the greater the difference in electronegativity, the greater the ionic character.

Molecular Compounds: molecules are made out of two or more anions. Covalent Bonds: two nonmetals must share electrons. VSEPR: valence shell electron pair repulsion. Shapes: lines represent a pair of two shared electrons. Linear Bent: 2 covalent bonds and 2 lone pairs Trigonal Planar: 3 covalent bonds and 0 lone pairs Pyramidal: 3 covalent bonds and 1 lone pair Tetrahedral: 4 covalent bonds and 0 lone pairs Polarity: oppositely charged ends. Polar Bond: between two different nonmetals with two different electronegativities. Cause each end to have a partial charge. Non Polar Bonds: between two of the same elements with the same electronegativity. No partial charges. Polar Molecule: the whole molecule can be split into oppositely partially charged pieces by drawing a straight line Nonpolar Molecule: the whole molecule cannot be split into oppositely charge pieces, but instead has a core with an opposite charge than its surroundings. Intermolecular Attractions: van der Wall forces, attractions between two separate molecules. Hydrogen Bonds: between 2 polar molecules with hydrogen Dipole Interactions: between 2 polar molecules without hydrogen Disperion Forces: between 2 nonpolar molecules Properties: low melting and boiling points, solids liquids and gases in nature, not conductors of electricity.

Metallics Bonds: between two metals who both want to lose electrons. Cations floating in a sea of free moving valence electrons. Properties: great conductors of electricity, solids, malleable, ductile.