chemistry VSEPR

octet rule

atoms will gain or lose electrons to have a full octet (8 valence)

nonpolar covalent

0.4 or less

polar covalent

0.4-2.0

ionic

2.0 or more

ionic bonds

cation and anion, compound results when a metal reacts with a nonmetal

covalent bonds

electrons are shared by nuclei

VSEPR theory

valence shell electron pair repulsion, electrons are arranged as far apart from eachother as possible

Linear

180, 2 bonds connected

bent

105, 1 double bond and one sinle bond and then a lone pair, 2 single bonds and 2 lone pairs

trigonal planar

120 degrees

tetrahedral

109.5, 2 single bonds, one bond headed towards you and one headed away

pyramidal

107, 1 single bond one headed towards you and one headed away

octahedral

90, 6 sides

trigonal bipyramidal

120 and 90, 5 sides

purple

boron

black

carbon

blue

nitrogen

green

halogen

white

hydrogen

red

oxygen

polar definition

electrons are shared unequally

nonpolar definition

electrons are shared equally; symmetrical

ionic electrons gained/lost

lost/gained

ionic types of atoms in bond

metal + nonmetal

ionic melting point

high

ionic dissolves in h2o

yes

other characteristics of ionic

brittle conductors

covalent electrons gaines/lost

sharing

covalent types of atoms in bond

nonmetals

covalent melting point

low

ovalent dissolves in h2o

no

other characteristics of covalent

nonconductors

why do metals and nonmetals usually form ionic compounds whereas two bonded nonmetals are never ionic

metals lose electrons and nonmetals gain electrons to achieve an octet

how to predict ionic, covalent, polar, nonpolar

determine element types, polar: 0.4-2.0, nonpolar: 0.4 or less

polyatomic ions

many atoms with a charge

common ions

the ion that forms by acheiving the octet