NONMETALS & METALLOIDS
Section 16-3
Exploring Nonmetals
Except for the noble (inert) gases,
most families of nonmetals also contain metalloids and/or metals,
so the families of nonmetals are not as similar in properties, as families of metals
Properties of Nonmetals
•Nonmetals make products with
a wide variety of properties
(fur, plants, plastics, liquids, gases)
sulfur
dull
•Mostly gases at room temp.
•Opposite physical properties
of metals: soft, dull, poor
brittle
conductors, brittle (break
easily), low densities.
•Most nonmetals react (gain or
NOT malleable or ductile,
share electrons) to form
Crumbles easily
compounds (except nobles)
Compounds of Nonmetals
• Some compounds - Nonmetals gain
electrons from metals (Na metal gives 1 veto Cl nonmetal to form the compound NaCl)
• Other compounds – nonmetals share
electrons with other nonmetals (CO or CO2)
• Diatomics – nonmetals share electrons
to form weak bonds with their “twin”;
7 elements: N2, O2, F2, Cl2, Br2, I2, & H2
Hydrogen is special!
H
1 ve-
• Hydrogen is a nonmetal and
belongs to a family of its own.
• Hydrogen is rarely found alone,
it is usually combined with
oxygen to form water
• Hydrogen is a simple, reactive
gas that will lose, gain, or share
1 valence electron.
• Hydrogen was involved in the
explosion of the Hindenberg.
• Hydrogen is promising as an
alternative fuel source for
automobiles
Carbon Family
•
•
•
•
Elements in group 14, (one nonmetal, two metalloids, & two metals)
Form compounds by losing, sharing, or gaining electrons
Contains elements important to life and computers.
Carbon is the basis for an entire branch of chemistry known as
organic chemistry
• Lead in household paints gave children lead poisoning
• Silicon is a semiconductor, highly used in the computer industry.
4 veC
Si
Ge
Sn
Pb
Nitrogen Family
• Elements in group 15, (two nonmetals, two metalloids, & one metal)
• Form compounds by sharing or gaining electrons
• Nitrogen makes up ¾ of the earth’s atmosphere as N2 ,
but this form is not available to living things
• Farmer use nitrogen rich soils for their crops, and we obtain
the nitrogen we need from those plants
• Nitrogen and phosphorus are both important in living things.
• Phosphorus is used to make matches and flares
5 veN
P
As
Sb
Bi
Oxygen Family
6 ve-
• Elements in group 16 (three nonmetals, one metalloids, & one metal)
• Oxygen is very reactive & forms compounds by sharing/gaining 2 ve• Oxygen is the most abundant element in the earth’s crust and
second most abundant element in the atmosphere
• Diatomic O2 is necessary for respiration and
triatomic O3 called ozone protects us from radiation from the sun
• Many things that stink, contain sulfur (rotten eggs, garlic, skunks, medicines)
O
S
Se
Te
Po
Halogens
F
Cl
Br
I
At
7 ve-
• Elements in group 17, very similar
• Mostly diatomic elements, “twins”
• Very reactive, volatile, nonmetals,
but useful in compounds
• Usually shares or gains 1 ve• Always found combined with other
element in nature (NaCl)
• Used disinfectants, to strengthen
teeth, in nonstick cookware
• Bromine is a liquid at room temp.
The Noble Gases
He
Ne
Ar
Kr
Xe
Rn
8 or 0 ve(2 ve- if He)
The Noble or Inert Gases
•
•
•
•
Elements in group 18
VERY UNREACTIVE gases
Have a full valence shell
First found in small amounts, in the
earth’s crust, in the late 1800’s
• Used in lighted “neon” signs
• Used in blimps to fix the Hindenberg
problem