The Periodic Table
gold
silver
helium
oxyge
n
mercury
hydrogen
sodium
nitrog
en
niobium
neodymium
chlorin e
Elements
Science has come
along way since
Aristotle’s theory of Air, Water, Fire, and Earth.
Scientists have
identified 90 naturally occurring elements, and created about 28 others.
Elements
The elements,
alone or in
combinations, make
up our bodies, our
world, our sun, and
in fact, the entire
universe.
The most abundant element in
the earth’s crust is oxygen.
What is the Periodic
Table?
It is an organizational system for
elements.
Periodic Table
The periodic table organizes the elements in a particular
way. A great deal of information about an element can be gathered from its position in the period table.
For example, you can predict with reasonably good
accuracy the physical and chemical properties of the element. You can also predict what other elements a particular element will react with chemically.
Understanding the organization and plan of the periodic
table will help you obtain basic information about each of the 118 known elements.
Who created it?
The quest for a systematic arrangement
of the elements started with the discovery of individual elements.
By 1860 about 60 elements were known
and a method was needed for organization.
In 1869, Russian chemist Dimitri
Mendeleev proposed arranging elements by atomic weights and properties.
The table contained gaps but Mendeleev
predicted the discovery of new elements.
So how is it arranged?
The genius of the periodic table “is that it
is organized like a big grid. The
elements
are placed in specific places because of
the way they look and act. If you have
ever looked at a grid, you know that there
are rows (left to right) and columns (up
and down). The periodic table has rows
and columns, too, and they each mean
something different.”
You've got Your Periods...
Even though they skip
some squares in
between, all of the rows
go left to right. When
you look at a periodic
table, each of the rows
is considered to be a
different
period
(Get it?
Like PERIODic table.)
quoted from
Periods = Rows
In the periodic table, elements have something in
common if they are in the same row.
All of the elements in a period have the same
number of
atomic orbitals
.
Every element in the top row (the first period) has
one orbital for its
electrons
. All of the elements in
the second row (the second period) have two
orbitals for their electrons. It goes down the
periodic table like that.
And you got your groups…
The periodic table
has a special name
for its columns, too.
When a column goes
from top to bottom,
it's called a
group
or families
.
quoted from
Groups = Columns
The elements in a group have the same number
of electrons in their outer orbital.
Every element in the first column (group one)
has one electron in its outer shell. Every element
on the second column (group two) has two
electrons in the outer shell. As you keep counting
the columns, you'll know how many electrons are
in the outer shell.
There are some exceptions to the order when
you look at the
transition elements
, but you get
the general idea.
Valence Electrons
The number of valence
electrons an atom has may also appear in a square.
Valence electrons are the
electrons in the outer energy level of an atom.
These are the electrons
that are transferred or shared when atoms bond together.
Created by G.Baker www.thesciencequeen.net
Lewis Dot Structure
The Lewis Dot
Structure is a bit
different from
the Bohr model.
It only shows the
element symbol
and it’s outer
most electron
shell.
O
• •
•
• •
•
+ + ++ + + ++ + + + + + + + + -- - -- --Symbols
All elements have
their own unique
symbol.
It can consist of a
single capital
letter, or a capital
letter and one or
two lower case
letters.
C
Carbon
Cu
Co = cobalt / cobalto
CO = carbon
monoxide /
monóxido de
carbono
What do all the numbers
mean ?
Other than periods and groups,
the table is divided into
families.
Alkali Metals
The alkali family is found in
the first column of the periodic table.
Atoms of the alkali metals
have a single electron in their outermost level, in other words, 1 valence electron.
They are shiny, have the
consistency of clay, and are easily cut with a knife.
•very reactive metals
that do not occur freely in nature
•malleable, ductile,
good conductors of heat and electricity.
•can explode if they
are exposed to water
ALKALI METALS
ALKALI METALS
What does it mean to be
reactive?
We will be describing elements according to their
reactivity.
Elements that are reactive bond easily with other
elements to make compounds.
Some elements are only found in nature bonded with
other elements.
What makes an element reactive?
An incomplete valence electron level.
All atoms (except hydrogen) want to have 8 electrons in their
very outermost energy level (This is called the rule of octet.)
Atoms bond until this level is complete. Atoms with few valence
electrons lose them during bonding. Atoms with 6, 7, or 8 valence electrons gain electrons during bonding.
Alkaline Earth Metals
They are never found uncombined in nature.
They have two valence electrons.
Alkaline earth metals include magnesium
•
metals
•
very reactive
•not found free
in nature
ALKLINE EARTH METALS
ALKLINE EARTH METALS
Transition Metals
Transition Elements
include those
elements in the B families.
These are the metals
you are probably most familiar: copper, tin, zinc, iron, nickel, gold, and silver.
Transition Metals
The compounds of transition metals are usually
brightly colored and are often used to color paints.
Transition elements have 1 or 2 valence electrons,
which they lose when they form bonds with other atoms. Some transition elements can lose electrons in their next-to-outermost level.
•
ductile and
malleable, and
conduct electricity
and heat
•
iron, cobalt, and
nickel, are the only
elements known to
produce a magnetic
field.
TRANSITION METALS
TRANSITION METALS
•
many are man-made
RARE EARTH ELEMENTS
RARE EARTH ELEMENTS
Rare Earth Elements
The thirty rare earth
elements are composed of the lanthanide and actinide series.
One element of the
lanthanide series and most of the elements in the actinide series are called trans-uranium, which means synthetic or man-made.
•
are ductile and
malleable
•
are solid, have
a high density,
OTHER METALS
OTHER METALS
Properties of Metals
Metals are good conductors
of heat and electricity.
Metals are shiny.
Metals are ductile (can be
stretched into thin wires).
Metals are malleable (can
be pounded into thin sheets).
A chemical property of
metal is its reaction with water which results in corrosion.
•have properties of both metals and
non-metals
•some of the metalloids are
semi-conductors. This means that they can carry an electrical charge under special conditions. This property makes
metalloids useful in computers and calculators
METALLOIDS
METALLOIDS
Properties of Metalloids
Metalloids (metal-like)
have properties of both metals and non-metals.
They are solids that can
be shiny or dull.
They conduct heat and
electricity better than non-metals but not as well as metals.
They are ductile and
malleable.
•not able to conduct electricity or heat very well •very brittle
•Do not reflect light.
NON-METALS
NON-METALS
Properties of
Non-Metals
Non-metals are poor
conductors of heat and electricity.
Non-metals are not
ductile or malleable.
Solid non-metals are
brittle and break easily.
They are dull.
Many non-metals are
gases.
Boron Family
The Boron Family is named
after the first element in the family.
Atoms in this family have 3
valence electrons.
This family includes a
metalloid (boron), and the rest are metals.
This family includes the
most abundant metal in the earth’s crust (aluminum).
Carbon Family
Atoms of this family have 4
valence electrons.
This family includes a
non-metal (carbon), non-metalloids, and metals.
The element carbon is called
the “basis of life.” There is an entire branch of chemistry devoted to carbon compounds called organic chemistry.
Nitrogen Family
The nitrogen family is named
after the element that makes up 78% of our atmosphere.
This family includes
non-metals, metalloids, and metals.
Atoms in the nitrogen family
have 5 valence electrons. They tend to share electrons when they bond.
Other elements in this family
are phosphorus, arsenic, antimony, and bismuth.
Oxygen Family
Atoms of this family have 6
valence electrons.
Most elements in this family
share electrons when forming compounds.
Oxygen is the most
abundant element in the earth’s crust. It is
extremely active and
combines with almost all elements.
•"halogen" means "salt-former" and compounds
containing halogens are called "salts"
•exist in all three states of matter
HALOGENS
HALOGENS
Halogen Family
The elements in this family
are fluorine, chlorine,
bromine, iodine, and astatine.
Halogens have 7 valence
electrons, which explains why they are the most active non-metals. They are never found free in nature.
Halogen atoms only need to gain 1 electron to fill their
outermost energy level. They react with alkali metals
•do not form compounds easily
•Happy/Inert Elements (Full outer shells)Happy/Inert Elements (Full outer shells)
NOBLE GASES
NOBLE GASES
Noble Gases
Noble Gases are colorless gases that are extremely un-reactive.
One important property of the noble gases is their inactivity. They are
inactive because their outermost energy level is full.
Because they do not readily combine with other elements to form
compounds, the noble gases are called inert.
The family of noble gases includes helium, neon, argon, krypton, xenon,
and radon.
Practice
Symbol Atomic Number(Z) Mass Number(A) Number of Protons(p+) Number of Electrons(e-) Number of Neutrons(N) Family PeriodRb 37 85
56 56 81
70 31
222 86
Hg 80
Practice
Word Definition Atomic Number
Chemical Symbol Element Name Mass Number
