Chapter 3 Sec 4
 Nonmetal
(not a metal)
Properties
--poor conductors
--reactive (readily form
compounds)
--dull
--brittle
10 of the 16 nonmetals
are gases at ROOM
TEMPERATURE

 Air
is a mixture of
nonmetals
 Solid
 Oxygen
and
Nitrogen
nonmetals
 Carbon,
Iodine,
Sulfur,
 Solids at room
temperature
Families
 Carbon
Family

Each atom in the
carbon family can
either GAIN, LOSE, or
SHARE 4 electrons in a
reaction

In group 14 only
Carbon is a nonmetal
Compounds made of
all carbon atoms are
found in EVERY living
thing

 Nitrogen
Family




Contains two
nonmetals; nitrogen
and phosphorus
Gain or Share three
electrons when
reacting with other
elements
Atmosphere is made
up of 80% nitrogen
Occurs in Nature
 Diatomic
Molecule



Consists of two
atoms
In this form nitrogen is
not very reactive
Living things need
nitrogen, however
most living things
cannot pull it from
the air
 Nitrogen




Certain kinds of
bacteria use nitrogen
to form compounds
This process is called
nitrogen fixation
Plants can then use
these nitrogen
compounds in the soil
Humans can get it from
the food we eat
 Phosphorus




Nonmetal in the
Nitrogen family
Very reactive
Always found in
compounds in
nature
Used to make
matches, because
Phosphorus can
react with the
oxygen in our air
 Oxygen
Family







Group 16
Contain 3 nonmetals
Oxygen, Sulfur,
Selenium
Diatomic molecule
Second most
abundant element in
the Earth’s atmosphere
Can be a triatomic
molecule (three atoms)
O3—Ozone
 Ozone
 Collects
in a layer
in the atmosphere
 Screens out
harmful radiation
from the sun
 DANGEROUS
pollutant at ground
level
 HIGHLY REACTIVE
 Halogen





Group 17
Fluorine, chlorine,
bromine, iodine,
astatine
“Salt forming”
elements
All nonmetals for
astatine
Gains or shares 1
electron when
bonding
 Halogens




Very reactive
Uncombined elements
are dangerous to
humans
Fluorine reacts with
almost every other
known substance
Chlorine gas is
extremely dangerous,
but in small amounts
can kill bacteria in
water
 Halogens




Compounds,
however, can be
quite useful
Carbon and fluorine
make up the
compound for
nonstick cookware
Small amounts of
fluorine prevents
tooth decay
NaCl is table salt
 Noble
Gasses





Group 18
Do not usually form
compounds
Because they are
stable elements
They do not gain,
lose, or share
electrons
All exist in Earth’s
atmosphere, but in
small amounts
 Noble
Gasses




 Hydrogen


Helium Balloons
Neon Lights
All made from noble
gas elements
Simplest and smallest
atoms
1 p+ and 1 eIt is so different it is
not usually grouped
 Metalloids




Border between
metals and
nonmetals
Some characteristics
of both metals and
nonmetals
All are solids at room
temp.
Brittle, Hard,
somewhat reactive
 Metalloids
Silicon, Boron (most
popular)
 Most useful property
is the ability to
CONDUCT electricity
 Changes depending
on several factors
-temp, exposure to
light, presence of small
impurities

 Semiconductors
 Substances
that
can conduct
electricity under
some conditions
but not under other
conditions
 Used to make
computer chips,
transistors, and
lasers