4.2 Valency + Oxidation States

oxidation state

positive/negative # that is reflected by the # of electrons either lost/gained by an atom

valency

ability of one atom of an element to join another atom in the formation of a new substance - absolute value of oxidation state

f block valence electrons - how many for all

2

High valency

-ic

Lower valency

-ous

what 2 factors effect coulumbs law

distance between particles and magnitude of charges

how many VE in elements in 4th period p block

2

1.) elements

oxidation of an atom in an element is 0

2.) monotomic ion

oxidation # of an atom in a monotomic ion equals the charge of the ion

3.) oxygen

oxidation # of oxygen is “-2” in most compounds, peroxide is “-1”

4.) hydrogen

oxidation # of hydrogen is “+1” in most compounds, “-1” with metals

5.) halogens

flourine is “-1” all other halogens are “-1” unless other element is halogen or oxygen

6.) compounds

sum of oxidation # of atoms in compound is 0, sum of polyatomic ion = charge of ion

Duet Rule

elements want 2 valence electrons to have noble gas config

Octet Rule

elements want 8 valence electrons to have noble gas config

Oxidation States 1st

holds 2, 2 unreactive

s block

Oxidation States 2nd

holds 8, 8 uncreactive

s + p block

Oxidation States 3rd

holds 32, 8 uncreative

s + p + d blocks

Oxidation States 4th

holds 32, 8 uncreactive

S + p + d + f blocks