Transcript Properties of the Periodic Table Families

Properties of the Periodic
Table Families
Chemistry Fall 2009
Octet Rule
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Atoms tend to gain, lose, or share e- in order
to get a full set of 8 valence eUseful for determining the type of ions likely to
form
Elements on the right side of the periodic table
tend to gain e-; forming negative ions
Elements on the left side of the periodic table
tend to lose e- and form positive ions
Why do elements on the right side gain e – and
elements on the left side lose e-?
Family 1A
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Alkali metals
Easily lose a valence eand form a ion with a
+1 charge
Soft enough to cut with
a knife
Highly reactive – too
reactive to be found
free in nature; good
conductors of heat and
electricity
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Example: NaCl in salt
water
Family 1A - Lithium
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Lightest alkali metal
Found in water, soil,
and rocks
Least reactive of alkali
metals
Compounds of lithium
found in batteries and
dehumidifiers
Used to strengthen
glass and treat bipolar
disorders
Hydrogen
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Placed in 1A because it
has 1 valence eH shares many
properties with
nonmetals and metals
Highly reactive
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Group 2A – Alkaline Earth Metals
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Form compounds with
oxygen called “oxides”
Shiny solids that are
harder than alkali
metals
Lose 2 valence e- to
form ions with a 2+
charge
Calcium
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Found widely in naturerocks, coral reefs
Needed to maintain
healthy teeth and
bones
Decomposition of
calcium carbonate
forms lime – used to
manufacture steel,
paper, and glass.
Magnesium
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Abundant
Can be formed into any
shape
Alloys are strong and
lightweight
Group 3A – The Boron Family
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Found in nature
combined with other
elements
B, Al, Ga lose 3 e- to
form ions with a +3
charge
Thallium loses only the
p valence e- to form
ions with a 1+ charge
Boron
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Borax comes from
California’s Mojave
Desert
Cleaning agent and
fireproof insulation
Boric acid used as
disinfectant and
eyewash
Boron nitride – 2nd
hardest known material
Super abrasives
Aluminum
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Most abundant metal in
earth’s crust
Recycling aluminum is
energy efficient
compared to extracting
it from its ore
Widely used – alum in
antiperspirants and
aluminum oxide in
many gems
Group 4A – The Carbon Group
Carbon
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Can form many
different compounds
Diamonds are hard,
graphite is soft –
allotrope
C atoms in graphite
share e- with other C
atoms to form layers
that slide
C atoms share e- with
other C atoms in
diamonds to form a 3-D
solid
Silicon
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Computer chips and
solar cells
Can be found in quartz
crystal, sand, and glass
Family 5A – The Nitrogen Group
Nitrogen
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Abundant in the
atmosphere
Proteins contain N
Bacteria in soil convert
N from the atmosphere
to nitrogen compounds
that are easier to use
by organisms
Ammonia – colorless
gas, irritating odor
Phosphorus
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Phosphate compounds
can be found in
cheese, laxatives,
baking powders, flameretardant fabric, grease
remover in cleaning
products
Essential for plant
growth (fertilizers) –
can be harmful to the
environment
Bismuth
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A compound of Bismuth
is an active ingredient
in a remedy for nausea
and diarrhea
Group 6A – The Oxygen Group
Oxygen
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6 valence e-; tend to
gain two e- to form ions
with a 2- charge; can
also share 2eOzone - unstable gas
Most abundant element
in Earth’s crust
Forms compounds with
every element except
He, Ne, and Ar
Sulfur
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Used to make acids to
be used in fertilizers,
steel, paper, and paints
Hydrogen sulfide used
as an energy source in
the ocean
Hydrogen sulfide
released from
volcanoes
Tarnish silver
Selenium
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Supplements
Found in eggs, fish,
and grains.
Works with vitamin E to
prevent cell damage
Used in solar cells converts light into
electricity
Locoweed – toxic levels
to grazing animals
copiers
Group 7A – The Halogens
Fluorine
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Form compounds with
almost all metals
Form ions with a 1charge
Added to toothpaste
and drinking water to
protect tooth enamel
from decay
Nonstick coating for
cookware
Chlorine
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Highly reactive
Deadly gas
Compounds of chlorine
are used as bleaching
agents, stain removal
Cl compounds are used
by dentists and
hydrochloric acid is
used to digest food,
rust removal, plastic
production
Iodine
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Body needs iodine to
maintain a healthy
thyroid gland
Seafood and iodized
salt are excellent
sources of iodine
Kills bacteria – used by
campers to disinfect
water
Group 8A – Noble Gases
Helium
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odorless and unreactive
Stable
Sun
Lightest noble gas
Used in blimps,
airships, and balloons
Neon
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Light displays
High-voltage electricity
passes through the
neon gas stored in a
gas discharge tube, ein the atoms become
excited
E- return to a lower
energy state and emit
bright light