| A | B |
|---|
| ionic bond | transfer of electrons from metals to nonmetals |
| electronegativity difference > 1.7 | ionic |
| electronegativity difference < 0.3 | nonpolar covalent |
| electronegativity difference 0.3 - 1.7 | polar covalent |
| formula unit | gives the ratio of cations to anions |
| covalent bond | pair of electrons is simultaneously attracted to two nuclei which results in lowering of potential energyelectron orbitals overlap, sharing a pair of electrons |
| bond length of a covalent bond | distance between two nuclei at the minimum potential energy level |
| polar covalent bond | chemical bonds in which electrons are shared unequally |
| nonpolar covalent bond | chemical bonds in which electrons are shared (fairly) equally |
| resonance structures | more than one Lewis dot structure for a molecule is possible |
| metallic bond | valence electrons are not bound to any particular cation, but are free to move throughout the metallic seal of electrons - must be a metal element usually in d block vicinity |
| properties of metals | good conductors of electricity & heat, ductile, malleable |
| alloy | metallic substances composed of two or more elements - at least one of these elements is a metal |
| lattice | give crystals their shape |
