Download The Periodic Table

The Periodic Table
PERIODIC
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appearing or occurring at intervals.
Why is it labeled the Periodic Table?
Name some things that are periodic:
It is periodic because there are
patterns that repeat each row or
period.
A BRIEF HISTORY
We have not always had the periodic
table.
The modern table as we know it is
only about 100 years old.
A BRIEF HISTORY
Father of the Periodic Table
DMITRI MENDELEEV
published 1869.
- He discovered a basic chemistry principle.
- He felt there was a certain pattern with
the elements.
- He tested his hypothesis that there was a
periodic relationship among the
elements.
- He set up the periodic table by ATOMIC
MASS and left blanks for undiscovered
elements (three were later discovered).
MENDELEEV’S TABLE
A BRIEF HISTORY
Father of the Modern Periodic Table
HENRY MOSELEY
1913
- He saw some elements were out of
place in Mendeleev’s table.
- He determined atomic numbers using xrays.
- The elements were placed according to
ATOMIC NUMBER. This was an
important change.
- This is the modern periodic table.
A BRIEF HISTORY
The Final Changes to the Table
Glenn Seaborg
 The last major change to the periodic table
resulted from Glenn Seaborg's work.
 Starting with plutonium in 1940, Seaborg
discovered transuranium elements 94 to
102 and reconfigured the periodic table by
placing the lanthanide/actinide series at
the bottom of the table.
 In 1951 Seaborg was awarded the Nobel
Prize in chemistry and element 106 was
later named seaborgium (Sg) in his honor.
Seaborg’s Contribution
WATCH

The Genius of Dmitri Mendeleev
PERIODIC TABLE
ORGANIZATION
Columns
- vertical, called groups
(numbers) or families
(names)
- 18 total (8 main ones)
- elements in the same column
are not identical, but similar in
properties.
PERIODIC TABLE
ORGANIZATION
ROWS
- horizontal, called periods,
- 7 total (at this time)
- elements are not alike in any way
PATTERN: left side elements are
active solids, far right side
elements are inert (nonreactive)
gases. Last two rows are rare
earth elements. Atomic number
increases from left to right.
1
2
3
4
5
6
7
6
7
ALTERNATIVE PERIODIC TABLES:
SPIRAL
ALTERNATIVE PERIODIC TABLES:
STOWE
ALTERNATIVE PERIODIC TABLES:
TARANTOLA
ALTERNATIVE PERIODIC TABLES:
MURADJAN
ALTERNATIVE PERIODIC
TABLES: CHEMICAL GALAXY
ALTERNATIVE PERIODIC
TABLES: 3D
CHARACTERISTICS OF
THE PERIODIC TABLE
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Gases: hydrogen, helium,
nitrogen, oxygen, fluorine,
chlorine, neon, argon, krypton,
xenon, radon.
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Liquids: mercury, bromine
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Solids: all the rest
PERIODIC TABLE
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Number the groups 1-18.
Number the periods 1-7.
Find element 92 (fourth one from the
left in the bottom most row).
Outline or lightly shade the elements
that appear AFTER it in the row.
Find the seventh period in the main
table. Outline or lightly shade the
elements that appear AFTER the first
two in the row.
PERIODIC TABLE
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You have just outlined the synthetic
elements,
artificial elements, called the
transuranium elements (“After”
uranium).
These are made in particle
accelerators.
VALENCE ELECTRONS
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The valence electrons are the
electrons in the outermost shell or
energy level of an atom.
The valence electrons are the ones
involved in forming bonds to
adjacent atoms.
Therefore, the number of valence
electrons is important for determining
the number of bonds an atom will
form.
VALENCE ELECTRONS
Group
Group
Group
Group
Group
Group
Group
Group
1
2
13
14
15
16
17
18
1
2
3
4
5
6
7
8
valence
valence
valence
valence
valence
valence
valence
valence
electrons
electrons
electrons
electrons
electrons
electrons
electrons
electrons
VALENCE ELECTRONS
VALENCE AND ELECTRON
DOT DIAGRAMS
Valence electrons = electrons in
outermost energy level of a Bohr
Diagram.
 Electrons in outermost energy level
of a Bohr Diagram = electrons in
electron dot diagram
SO
 Valence electrons = electrons in
electron dot diagram
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VALENCE AND ELECTRON
DOT DIAGRAMS
Element
1.
Lithium
1.
Fluorine
1.
Aluminum
Period
Group
Valence
Electrons
Electron Dot
Diagram
We will look at how to draw
electron dot diagram Wednesday.
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Skip the last column if you need to
for now.
ANOTHER WAY TO LOOK AT
THE TABLE
All elements can be divided into three
groups:
METALS
NONMETALS
METALLOIDS
METALS
METALS
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located on the left side and center.
good conductors of heat and electricity.
hard and shiny (not always silver)
can be pounded into different shapes malleable
can be drawn into a wire - ductile
high density, high melting points
react with water and substances in the
atmosphere
(ex. rusting, tarnishing)
METALS
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has only a few electrons in the outer
level
most elements are metals.
General rule: 3 or fewer electrons in
outer level are considered to be metals.
Metals have a tendency to lose
electrons when forming compounds.
NONMETALS
NONMETALS
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located on the right side (except
hydrogen)
poor conductors of heat and
electricity (solids are insulators)
brittle solids or gases or liquids
dull
shatter easily
lower density, lower melting points
NONMETALS
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o
o
not as easy to recognize as a group
has more than 4 electrons in the
outer level.
General rule: 5 or more electrons in
outer level are considered to be
nonmetals.
Nonmetals have a tendency to gain
electrons when forming compounds
METALLOIDS
METALLOIDS
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Sometimes called semi-metals.
have properties of metals and
nonmetals
“metal-like”
located on either side of the
staircase
all are shiny, white-gray in color
all are solids
okay conductors (as in semiconductors), ductile, malleable
METALLOIDS
There are seven:
Boron, Silicon, Germanium,
Arsenic, Antimony, Tellurium,
Astatine
Aluminum is NOT a metalloid.
Polonium is sometimes classified as
a metalloid.
METALLOIDS
UNKNOWN METALS LAB
Introduction: Most of the elements on
the periodic table are metals and solids.
These elements have observable
properties that make it possible to
identify an unknown element. Density
is one of the properties that can be
used to identify an unknown metal. As
you know, density is the ratio of mass
to volume. In equation form: Density =
Mass ÷ Volume.
THE ELEMENT FAMILIES
HYDROGEN – a special case
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one valence electron
Considered a nonmetal;
Not part of Group One;
acts as a metal and a nonmetal;
most abundant element in the
universe;
flammable
ALKALI METALS – group 1
GROUP 1: ALKALI METALS
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Early in human history, people
discovered that ashes mixed with water
produced a slippery solution useful for
removing grease.
By the Middle Ages, such mixtures were
described as alkaline, a term derived
from the Arab word for ashes, al-qali.
Alkaline mixtures found many uses,
particularly in the preparation of soaps.
This is why they are called alkali metals.
We now know that alkaline ashes
contain compounds of Group 1
elements, most notably potassium
carbonate (potash).
ALKALI METALS – group one
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one valence electron;
very reactive
Most reactive is francium;
not found in nature by themselves;
low electron affinity
SODIUM and POTASSIUM important
to body functions
FRANCIUM – most reactive metal, but
extremely rare
GROUP TWO:
ALKALINE EARTH METALS
ALKALINE EARTH METALS –
group two
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Elements in group 2 also form alkali
solutions when placed in water.
Medieval alchemists noted that
certain minerals do not melt or
change when put into fire – we
know these as group 2 elements.
These fire-resistant substances
were known to alchemists as earth.
As a holdover from these ancient
times, group 2 elements are known
as alkaline earth metals.
ALKALINE EARTH METALS –
group two
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two valence electrons;
less reactive, but similar to alkali
metals;
low electron affinity,
CALCIUM – 5th most abundant
element on earth (lime, calcium
chloride, body functions)
GROUPS 3-12:
TRANSITION ELEMENTS
TRANSITION ELEMENTS –
groups 3-12
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The elements in groups 3-12 are all
metals that do not form alkaline
solutions with water.
These metals tend to be harder than
alkali metals and less reactive with
water.
They are used for structural purposes.
Their name – transition metals – denotes
their central position in the periodic
table.
TRANSITION ELEMENTS –
groups 3-12
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Two, three, or four valence e-;
They all have properties similar to one
another and to other metals: resistant
to corrosion, high melting points,
brittle
These metals are less reactive than
Group 1 or 2, and are harder.
Include IRON (steel), CADMIUM
(batteries), COPPER (wiring), COBALT
(magnets), SILVER (dental fillings),
ZINC (paints), GOLD (jewelry)
GROUP 13: Boron Family
Boron Family – group 13
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three valence electrons
includes metalloids and metals
BORON – metalloid;
ALUMINUM – most plentiful
metal in the earth's crust, has the
most practical uses
GALLIUM – low melting point,
component of blue lasers.
GROUP 14: CARBON FAMILY
CARBON FAMILY – group 14
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four valence electrons;
generally react by sharing electrons,
Consists of a nonmetal, metalloids,
and metals;
CARBON – most versatile element can
form millions of compounds; field of
organic chemistry; has several
allotropes: graphite, diamond, fullerene,
carbon black
SILICON – second most plentiful
element in the earth’s crust (quartz);
many industrial uses.
LEAD – toxic; used to be in paint,
plumbing, gasoline
GROUP 15: NITROGEN FAMILY
also called Pnictogen Family
NITROGEN FAMILY – group 15
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five valence electrons;
Consists of nonmetals,
metalloids, and a metal
Sometimes will share its five
electrons
NITROGEN – found in fertilizers,
TNT, medicines, proteins
PHOSPHORUS – compounds
found in laxatives, cheese, and
baking powders
GROUP 16: OXYGEN FAMILY
also called Chalcogens
OXYGEN FAMILY – group 16
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six valence electrons;
Consists of nonmetals and
metalloids
OXYGEN - very reactive; most
plentiful element in the earth’s
crust; forms compounds with
practically every element (except
neon, argon, and helium); has two
allotropes, O2 and O3.
ALLOTROPES
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Different forms of the same
element.
Examples:
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Oxygen,O2 and ozone, O3
Carbon – diamond, graphite, charcoal
DIATOMIC MOECULES
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a molecule that consists of two
atoms of the same element.
There are seven diatomic
molecules: H2, N2, O2, F2, Cl2, Br2,
and I2
Noble gases are NOT diatomic.
DIATOMIC MOLECULES
GROUP 17: HALOGEN FAMILY
HALOGEN FAMILY – group 17
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Called Halogens - Swedish for “salt-forming”;
seven valence electrons
high electron affinity,
FLUORINE - most reactive nonmetal
(element) due to its size; most
electronegative element; reacts with all
elements but neon, helium, and argon.
CHLORINE – deadly gas; compounds act as
bleaching agents and disinfectants
IODINE – used to disinfect water and
wounds (tincture of iodine)
GROUP 18:
NOBLE GAS FAMILY
NOBLE GAS FAMILY – group 18
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Nonreactive gases that tend not to
combine with other elements.
They are called the Noble gases,
presumably because the nobility of
early times were above interacting
with the common people.
NOBLE GAS FAMILY – group 18
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eight valence electrons (except
Helium which has two)
has stable outer electron
configurations and all electron
energy levels are full;
low electron affinity
HELIUM – used in scuba diving;
balloons
NEON, ARGON – lighting
INNER TRANSITION ELEMENTS
– no group number
INNER TRANSITION ELEMENTS
– no group number
INNER TRANSITION ELEMENTS
– no group number
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In the sixth and seventh periods, there are a
subset of 28 metallic elements that are quite
unlike any of the other transition elements.
Inserting the inner transition elements into
the main body of the periodic table results in
a long and cumbersome table, so these
elements are pulled out below the table so it
can fit nicely on a 8.5” x 11” piece of paper.
These two rows have no group number.
INNER TRANSITION ELEMENTS
– no group number
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The elements in each subset have
properties that are so similar to one
another that each subset can be
viewed as a group.
Include the Lanthanides and the
Actinides, names after the first
element in each group.
INNER TRANSITION ELEMENTS
– no group number
LANTHANIDES:
 silvery metals with high melting
points
 high luster and conductivity
 Tend to be mixed together in the same
geologic zones and are hard to
separate since they are so similar;
 used in making high quality glass,
television screens, lasers, tinted
sunglasses, LEDs
INNER TRANSITION ELEMENTS
– no group number
ACTINIDES:
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Have similar properties and are not easily
purified. This is a problem for the nuclear
industry as it requires purified samples of
uranium and plutonium.
all are radioactive
93-103 are synthetic (transuranium
elements)
Most common are URANIUM and
PLUTONIUM - used as nuclear fuel.
PERIODIC TRENDS
OR
Why we call it the PERIODIC table
PERIODIC
REMEMBER:
 It is periodic because there are
patterns that repeat each row or
period.
PERIODIC TRENDS
Elements have properties because of their
atomic number which tells the number
of electrons and thus the valence
electrons.
 Same column = similar valence electrons
Properties that are periodic:
metals/metalloids/nonmetals, boiling
point, density, atomic radii, ionic radii,
oxidation numbers, ionization energies,
electron affinities, electronegativity
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Boiling Point of the Elements
IONIZATION ENERGY
ALKALI METALS
Which element had the largest
reaction?
Any idea why?
ATOMIC RADII (size)
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As the electron energy levels increase down
a group, the period number increases ,
and so does the atomic radii.
As the atomic number increases across a
period, the positive charge also increases
within the same energy level and so the
electrons are more attracted to the nucleus
TREND: atomic radii increases down a
group, atomic radii decreases across a
period.
ATOMIC RADII
ELECTRON AFFINITY
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The attraction of an atom for an electron.
If an element has a high electron affinity, it
really wants to gain an electron.
TREND:
 Metals have LOW electron affinities
 Nonmetals have HIGH electron affinities
(except the Noble Gases).
SUMMARY
Noble Gases:
- Eight valence electrons (except
helium)
- atomic radii
large for their row
- Electron Affinity
LOW
SUMMARY
Halogens:
- Seven valence electrons
- atomic radii
lowest for their row
- Electron Affinity
HIGH
SUMMARY
Alkali Metals
- one valence electron
- Atomic radii
largest for their
row
- Electron Affinity
LOW
SUMMARY
Alkaline Earth metals:
- two valence electrons
- Atomic radii second largest for
their row
- Electron Affinity
LOW
Thanks to Mrs. Brim at East Jackson for the periodic Table Notes!