Unit 3 The Periodic Table

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The Periodic
Table of The
Elements
The Periodic
Table

Arrangement of the known elements
based on atomic number and chemical
and physical properties.

Divided into three basic categories:
 Metals
 Nonmetals
 Metalloids
Basic Organization
The periodic table is organized by:
Atomic structure
 Atomic number
 Chemical and Physical Properties

Uses of The Periodic Table
The periodic table is useful in
predicting:



chemical behavior of the
elements
trends
properties of the elements
Atomic Structure Review

Atoms are made of protons,
electrons, and neutrons.

Elements are atoms of only one type.

Elements are identified by the atomic
number (# of protons in nucleus).
Energy Levels Review

Electrons are arranged
in a region around the
nucleus called an
electron cloud. Energy
levels are located within
the cloud.

At least 1 energy level
and as many as 7 energy
levels exist in atoms.
Energy Levels Review

Electrons in levels farther away from
the nucleus have more energy.

Inner levels will fill first before outer
levels.
Energy Levels & Valence Electrons

Energy levels hold a
specific amount of
electrons:
1st level = up to 2
 2nd level = up to 8
 3rd level = up to 8 (first
18 elements only)

Energy Levels & Valence Electrons

The electrons in the outermost level
are called valence electrons.


Determine reactivity - how elements will react
with others to form compounds
Outermost level does not usually fill
completely with electrons
Due Today
Two column notes save as a PDF
 Video watched with comment


Due Tomorrow
Interpreting the Periodic Table
 Warm Up Log
 Current Event

Elements & Reactivity

Reactivity is a chemical property that
determines how elements will react
with others to form compounds.
Elements & Reactivity

What makes an element reactive?
●
●
●
Number of valence electrons each
atom has
When outer levels are full, atoms are
stable.
When they are not full, they react:
●
gain, lose, or share 1 or 2 electrons.
Elements & Reactivity

The most reactive metals are the
elements in Groups 1 and 2.



Video
http://www.youtube.
com/watch?v=xxi6k
Ubvo94
Elements in Group 1 need seven
more electrons to fill their outer
level.
Elements in Group 2 need six
more electrons to fill their outer
level.
These groups are known as the
“givers” because they easily give up
their valence electrons to make a
compound.
Elements & Reactivity

The most reactive nonmetals are the
elements in Groups 16 and 17.



Fluorite
Elements in Group 16 only need
two more electrons to fill their
outer level.
Elements in Group 17 only need
one more electron to fill their
outer level.
These groups are known as the
“takers” because they easily receive
valence electrons to make a
compound.
Using the Table to Identify
Valence Electrons



Elements are grouped into vertical columns
because they have similar properties.
These are called groups or families.
Groups are numbered 1-18.
Using the Table to Identify
Valence Electrons

Group numbers can help you
determine the number of valence
electrons:
 Group 1 has 1 valence
electron.
 Group 2 has 2 valence
electrons.
 Groups 3–12 are transition
metals and have 1 or 2 valence
electrons.
Using the Table to Identify
Valence Electrons cont.

Groups 13–18 have 10 fewer than the group number. For
example:



Group 13 has 3 valence electrons.
Group 15 has 5 valence electrons.
Group 18 has 8 valence electrons.
Switch
to Mimio
Group 1: Alkali Metals
Contains: Metals
 Valence Electrons: 1
 Reactivity: Very Reactive
 Properties:

solids
 soft
 react violently with water
 shiny
 low density

Sodium
Group 2: Alkaline-Earth Metals
Contains: Metals
 Valence Electrons: 2
 Reactivity: very reactive,
but less reactive than alkali
metals (Group 1)
 Properties:

Solids
 Silver colored
 More dense than alkali
metals

Magnesium
Groups 3-12 Transition
Metals
Contain: Metals
 Valence electrons: 1 or 2
 Reactivity: less reactive than
alkali and alkaline-earth
metals
 Properties:

Higher density
 Good conductors of heat and
electricity

Copper
Groups 3-12 Transition Metals
Below Main Table

Contain: The Lanthanide and
Actinide Series
These two rows are pulled out
of sequence and placed below
the main table to keep the table
from being too wide.
 Lanthanides are #’s 58–71.
 Actinides are #’s 90–103.

Plutonium
Groups 3-12 Rare Earth
Elements ~ Lanthanides
Lanthanides follow the
transition metal # 57
Lanthanum in Period 6.
 Valence electrons: 3
 Reactivity: Very reactive
 Properties:

●
●
Cerium
●
High luster, but tarnish easily
High conductivity for
electricity
Very small differences
between them
Groups 3-12 Rare Earth
Elements ~ Actinides
Actinides follow the
transition metal # 89
Actinium in Period 7
 Valence electrons: 3
(but up to 6)
 Reactivity: unstable

All are radioactive
 Most made in
laboratories

Uranium
Metalloids
A zig-zag line that
separates metals from
metalloids
 Elements from Groups 13–
17 contain some
metalloids.


These elements have
characteristics of metals
and nonmetals.
Group 13: Boron Group
Group 13: Boron Group
 Contains: 1 metalloid and 4
metals
 Valence Electrons: 3
 Reactivity: Reactive
 Other shared properties:


Boron
Solid at room temperature
Group 14: Carbon Group
Contains: 1 non-metal, 2
metalloids, and 3 metals
 Valence Electrons: 4
 Reactivity: Varies
 Other shared properties:


Carbon
Solid at room temperature
Group 15: Nitrogen Group
Contains: 2 non-metals, 2
metalloids, and 1 metal
 Valence electrons: 5
 Reactivity: Varies
 Other shared properties:


Nitrogen
All but N are solid at room
temperature
Group 16: Oxygen Group
Contains: 3 non-metals, 1
metalloid, and 2 metals
 Valence Electrons: 6
 Reactivity: Reactive
 Other shared properties:


Oxygen
All but O are solid at room
temperature.
Groups 17 : Halogens
Contain: Nonmetals
 Valence Electrons: 7
 Reactivity: Very reactive
 Other shared properties

●
●
●
Chlorine Gas
Poor conductors of electric
current
React violently with alkali
metals to form salts
Never found uncombined in
nature
Group 18 Noble Gases
Contains: Nonmetals
 Valence Electrons: 8 (2
for He)
 Reactivity: Unreactive
(least reactive group)
 Other shared properties:

Colorless, odorless gases
at room temperature
 Outermost energy level full
 All found in atmosphere

Neon
Hydrogen Stands Apart




Hydrogen in it’s
Plasma state
H is set apart because its
properties do not match
any single group.
Valence electrons: 1
Reactivity: very, but loses
the 1 electron easily
Properties:
 Similar to those of nonmetals rather than
metals
Warm Up

WAIT TO TURN THIS IN!!!!!!!!!!!!!!!!
Due Today

Due Today
Two column notes save as a PDF
 Warm Up Log saved as a PDF
 Current Event
 Video watched with comment
 Interpreting the Periodic Table

Periods
Periods run horizontally across the
Periodic Table
 Periods are numbered 1–7
 All the elements in a period will have
the same number of energy levels,
which contain electrons. Examples:

Period 1 atoms have 1 energy level.
 Period 2 atoms have 2 energy levels.
 Period 5 atoms have 5 energy levels.

Mimio
Periods Continued

Moving from left to right across a period,
each element has one more electron in
the outer shell of its atom than the
element before it.

This leads to a fairly regular pattern of
change in the chemical behavior of the
elements across a period.
Mimio
Quiz Quiz Trade
Brief History of the
Periodic Table
Brief history of the periodic Table
When
Who
What
Ancient Greece
In Ancient Greece, people believed
that there were only four elements…..
 Earth
 Fire
 Water
 Air

What were scientist looking for when they
found the first element
Alchemists
 They were looking for the
philosopher’s stone, which reputedly
could change base metals into gold

Hennig Brand
1649
 Made the first scientific
discovery of an element
 Phosphorus
 He isolated from urine, a
white, waxy material and
named it phosphorus
(“light bearer”), because
it glowed in the dark.

A.E. Beguyer de Chancourtois
1817
 Listed elements on a cylinder in order
of increasing atomic mass

Johann Dobereiner





1862
Proposed there were triads of three elements
in nature with the mass of the middle element
being the average of the other two
Law of Triads
Found that the properties of bromine seem
halfway between those of chlorine and iodine.
He showed that in each triad the mean of the
lightest and heaviest atomic weights
approximated the atomic weight of the middle
element.
In other words…. 4………6.......8
John Newlands
1863
 Classified the 56 known elements into
a table with 11 groups based on
properties. He proposed that any
element will behave similar to the 8th
element following it.


Law of Octaves
Lothar Meyer




1864, German
Developed a shortened
version of the table only
showing half of the known
elements.
Elements were listed in
order of atomic mass and
differences in behavior
were due to mass.
He published a longer
version in 1869 but it
wasn’t published until
1870
Dmitri Ivanovich Mendeleev




1869, Russian
Rearranged elements
in order of their
properties.
He showed a vertical,
horizontal and
diagonal relationship
between the 63
known elements
Predicted three yetto-be-discovered
elements including
eke-silicon and ekeboron
Lord Rayleigh
1895
 Discovered argon and
found it didn’t fit in the
current groups.
 In 1898 he proposed a
new group to be called
zero group because
argon was unreactive
(inert)

Ernest Rutherford
1911
 Studied nuclei
which led to the
concept of nuclear
charge
 Positive Charge
and Protons

Henry Mosely



1913
Published results
of x-ray
wavelengths of
elements which
proved the
elements are in
order of atomic
number.
He used
increasing atomic
numbers and not
atomic masses
Glenn Seaborg






1940
Discovered plutonium and all
elements from 94-102.
He moved the Lanthanides and
Actinides below the table.
Discovered 10 different elements to
include seaborgium, which was
named after him
credited with important
contributions to the chemistry of
plutonium, part of the Manhattan
Project where he helped develop
fuel for the second atomic bomb
pioneer in nuclear medicine, most
notably iodine-131, which is used in
the treatment of thyroid disease.
Quiz Quiz Trade
Various Periodic Table
Go to this website and look at the
different periodic tables for the rest of
class
 http://www.metasynthesis.com/webbook/35_pt/pt_data
base.php?Button=pre1900+Formulations

Warm Up
Brief History of the Periodic
Table

Did the grouping change once you
started posting them on the board?

Was it easier to group the atoms once
you understood the property needed
to group them?

Do you think that the periodic table will
remain in the same form as it is now?
Patterns

Next blank page of you spiral title
Patterns

Number 1-5 and leave 3 lines between
each number
Periodic Trends

What does periodic mean?


What does trend mean?


Are the tendencies of certain characteristics of
the atoms to increase or decrease along a row
or column of the periodic table of elements
What are some of the patterns found in the
periodic table?


A pattern of gradual change or movement
What might be a good definition for
periodic trends?


Recurring at regular intervals
Average atomic mass increases right to left
and top to bottom
How does the arrangement of the periodic
table allow for the prediction of
undiscovered elements and their
properties?

patterns




Atomic Number INCREASES
Metalic Properties INCREASES
Valence Electrons Down a Group
Remain the Same
Valence Electrons Across a
Period INCREASE
Warm Up
Agree or Disagree and Why

The following elements all belong to the same period:
Ne, Ar, Kr, and Xe.


The following elements all belong to the same
group/family: H, Li, Na, and K.


Agree because they all have the same number of
valence electrons.
All elements in group 13 have 3 valence electrons.


Disagree because they all have different numbers of
energy levels.
Agree because all elements in group 13 have ten less
than stated, and all elements in a group have the same
number of valence electrons.
The chemical reactivity of an element is determined by
its protons.

Disagree because the reactivity is determined by the
number of valence electrons
Warm Up
Study your spiral
 Write “Test” on your warm up log

After the Test
Turn in your spiral on lab table 2
 STAY QUEIT
 You may read, work on homework, or
log on to study island
 If we have time I will check your
grades after the test

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