Nonmetals, inert gases,
and semimetals
Exploring the right side of the periodic table.
Properties of non metals
• Nonmetals lack the
properties of metals.
• Most nonmetals are
poor conductors of
both heat and
electricity.
• Nonmetal solids are
brittle and are dull in
color. (Sulfur)
• Many nonmetals are
common Earth
elements.
Physical properties
• Four nonmetals are gases
at room temperature
(oxygen, nitrogen, fluorine,
and chlorine).
• Other nonmetals are solids
at room temperature
(carbon, iodine, and sulfur).
• Bromine is the only
nonmetal which is a liquid at
room temperature.
Chemical properties
• Atoms of nonmetals
either gain or share
electrons when they
react with other
elements.
• Examples of these
types of reactions are
salt (NaCl) and rust
(Fe2O3).
Families of the Non metals
(The Boron Family)
• These elements usually
share or donate their
three electrons in the
valence shell.
• The family extends from
Boron to Ununtrium
(#113).
• One of the most
commonly used
elements from this family
is Aluminum.
(The carbon family)
• The elements in the
carbon family all like
to share, gain, or lose
four electrons.
• The Family extends
from carbon through
lead.
• Carbon is the basis of
all of the life on the
planet Earth.
Why is Carbon so important to life
on planet Earth?
• Because carbon has the unique
ability of being the only
nonmetal which can generate
four bonds it can form long
chains to produce many
different substances.
• Proteins, oil, carbohydrates,
and coal are examples of
important substances which are
made of long chains of
carbons.
The nitrogen family
• This group contains two nonmetals
nitrogen and phosphorous, which are both
important to plants and agricultural growth.
• The elements in this family usually share
or gain three electrons.
• The Earths atmosphere is about 80%
nitrogen gas.
• Nitrogen occurs in nature as N2 which is
called a diatomic molecule. In this form the
N2 gas is not very reactive.
• Some bacteria use nitrogen as the basis to
form compounds to keep themselves alive
(Nitrogen fixation).
• Match heads are made of phosphorous
which is very reactive when struck and lit.
The oxygen family
• The oxygen family contains three
nonmetals (oxygen, sulfur, and selenium).
• These elements usually gain or share two
electrons.
• Oxygen is one of the most important
elements which keeps the human species
alive.
• Oxygen, like nitrogen is a diatomic
molecule (O2), and can also form a
triatomic molecule (O3) called ozone.
• Oxygen is very reactive and can combine
with most other elements.
• Oxygen is the most abundant element in
the Earths crust and the second most
abundant in the atmosphere.
• Sulfur which is another member of the
Oxygen family which is used to make
Sulfuric acid (H2SO4)
The halogen family
• Group 17 contains fluorine, chlorine,
bromine, iodine, and astatine.
• Halogen actually means “salt
forming”
• Halogens gain or shares only one
electron with other elements to make
compounds.
• Halogens are very dangerous when in
a pure form.
• Example of dangerous halogens are
bromine which can cause significant
burns, bromine also reacts with silver
to produce photos and images on xray film.
Inert gases
• The elements in group 18 are the inert
gases.
• The other name for the inert gases are
the “noble gases”
• These gases do not usually share, gain,
or lose any electrons.
• The inert gases tend to be very
unreactive.
• These gases are so unreactive they were
not discovered until the late 1800s’.
• Common uses for noble gases are neon
signs (also xenon, and argon).
• Also helium is used in helium balloons.
Hydrogen
• Hydrogen lacks a neuron and
contain only one proton.
• Although it makes up 90% of the
universe, it actually makes up less
that 1% of the Earths crust.
• Most hydrogen is bound to oxygen
to produce water.
• Because hydrogen has some
unique properties it is not placed in
a particular group. Hydrogen can
combine with most every other
element, so it is reactive, but it is a
gas, so it is placed in the far left
corner of the periodic table by itself.
Semimetals
• Semimetals are between metals and
nonmetals.
• These elements have characteristics of
both groups.
• The most common metal is silicon (Si).
• The most common place to find silicon is at
the beach which is silicon dioxide or SiO2,
which is called sand.
• Semimetals are semiconductors which
means they conduct electrical current
under certain conditions.
• The semiconduction characteristic of the
semimetals is the reason why elements like
Silicon and Gemanium are used for
computer chips, lasers, and transistors.