Untitled - Kelly Walsh High School

286 CHEMISTRY FOR THE UTTERLY CONFUSED
values for the nonmetals increase toward the top of any column and towards
the right on the periodic table. Fluorine has the highest electronegativity. The
noble gases do not have an electronegativity value.
Chemically, nonmetals are usually the opposite of metals. The nonmetallic
nature will increase towards the top of any column and toward the right in any
row on the periodic table. Most nonmetal oxides are acid anhydrides. When
added to water, they will form acids. A few nonmetals oxides, most notably CO
and NO, do not react. Nonmetal oxides that do not react are neutral oxides.
The reaction of a nonmetal oxide with water is not an oxidation-reduction reaction.
The acid that forms will have the nonmetal in the same oxidation state as
in the reacting oxide. The main exception to this is NO 2, which undergoes an
oxidation-reduction (disproportionation) reaction to produce HNO 3 and NO.
When a nonmetal can form more than one oxide, the higher the oxidation number
of the nonmetal, the stronger the acid it forms.
19-7 Properties of the Transition Metals
The most confusing property of the transition metals is that nearly every transition
metal can adopt more than one oxidation state. In most cases, the range of
oxidation states is from 2 to the group number if you use the older system of
assigning group numbers with Roman numerals. The maximum oxidation number
in the first transition series is 7 (manganese), while the highest in the second
and third transition series is 8 (ruthenium and osmium). For all three series,
you should expect the upper limit to increase to the maximum for the series and
then start decreasing. The only 1 oxidation states are in column IB (11) where
the three metals, copper, silver, and gold, may adopt this state. The 1 state is the
most stable state for silver. Zinc and cadmium use only the 2 oxidation state.
The mercury(I) ion, Hg 2 2 , is a special case because it is a polyatomic ion. Since
there are multiple oxidation states available, you must have additional information
in the problem or chapter in order to know which one you should choose.
Compounds or ions with the metal in an oxidation state above 5 are strong oxidizing
agents. The ions Ti 3 , V 2 , Cr 2 , and Fe 2 are reducing agents.
19-8 Coordination Compounds:
Crystal Field Theory
In addition to the ability of transition metals to adopt a variety of oxidation states,
they have the ability to form coordination compounds. Coordination compounds
contain complex ions. The ability to form a complex ion is not restricted to transition
metals; however, most examples you will see involve a transition metal.