Chemistry 1027A/B Chapter Notes -Chemical Polarity, Covalent Bond, Lewis Structure
Document Summary
Organic chemistry: study of the compounds of c. An atom consists of a small, dense nucleus and electrons concentrated about the nucleus in regions of space called shells. Lewis structure of an element shows symbol of the element surrounded by a number of dots equal to the number of e- in its valence shell. Ionic bond: chemical bond formed by attractive force between anion and cation. Covalent bond: chemical bond formed by sharing of e- pairs between atoms. Tendency of main group elements to achieve an outer shell of 8 valence e- (octet rule) Electronegativity: measure of the forces of attraction by an atom for e- it shares in a chemical bond with another. Vsper predicts bond angles of 109. 5 about atoms surrounded by 4 regions of electron density, 120 for 3 regions and 180 for 2 regions: common shapes for small molecules include tetrahedral, pyramidal, linear, and bent.