The Periodic Table of The Elements. Arrangement of the known elements based on atomic number and...
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Transcript of The Periodic Table of The Elements. Arrangement of the known elements based on atomic number and...
The Periodic Table of
The Elements
Arrangement of the known elements based on atomic number and chemical and physical properties.
Divided into three basic categories:MetalsNonmetalsMetalloids
The Periodic Table
Basic Organization
The periodic table is organized by:
Atomic structureAtomic numberChemical 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 ReviewAtoms 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 ReviewElectrons 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 PDFVideo watched with comment
Due TomorrowInterpreting the Periodic TableWarm Up LogCurrent 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.
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.Video
http://www.youtube.com/watch?v=xxi6kUbvo94
Elements & Reactivity The most reactive nonmetals are
the elements in Groups 16 and 17.
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.
Fluorite
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 MetalsContains: MetalsValence Electrons: 1Reactivity: Very
ReactiveProperties:
solidssoftreact violently with watershiny low densitySodium
Group 2: Alkaline-Earth Metals
Contains: MetalsValence Electrons: 2Reactivity: very reactive,
but less reactive than alkali metals (Group 1)
Properties: SolidsSilver coloredMore dense than alkali
metalsMagnesium
Groups 3-12 Transition Metals
Contain: MetalsValence electrons: 1 or 2Reactivity: less reactive
than alkali and alkaline-earth metals
Properties:Higher densityGood conductors of heat and
electricityCopper
Groups 3-12 Transition MetalsBelow Main Table
Contain: The Lanthanide and Actinide SeriesThese 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: 3Reactivity: Very reactiveProperties:
● High luster, but tarnish easily ● High conductivity for
electricity● Very small differences
between them
Cerium
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: unstableAll are radioactiveMost made in
laboratoriesUranium
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 GroupContains: 1 metalloid and 4
metalsValence Electrons: 3Reactivity: ReactiveOther shared properties:
Solid at room temperature
Boron
Group 14: Carbon Group
Contains: 1 non-metal, 2 metalloids, and 3 metals
Valence Electrons: 4Reactivity: VariesOther shared properties:
Solid at room temperature
Carbon
Group 15: Nitrogen Group
Contains: 2 non-metals, 2 metalloids, and 1 metal
Valence electrons: 5Reactivity: VariesOther shared properties:
All but N are solid at room temperature
Nitrogen
Group 16: Oxygen Group
Contains: 3 non-metals, 1 metalloid, and 2 metals
Valence Electrons: 6Reactivity: ReactiveOther shared properties:
All but O are solid at room temperature.
Oxygen
Groups 17 : Halogens
Contain: NonmetalsValence Electrons: 7Reactivity: Very reactiveOther shared properties
● Poor conductors of electric current
● React violently with alkali metals to form salts
● Never found uncombined in natureChlorine Gas
Group 18 Noble Gases
Contains: NonmetalsValence 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 atmosphereNeon
Hydrogen Stands Apart
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 non-
metals rather than metals
Hydrogen in it’s Plasma state
Warm Up
WAIT TO TURN THIS IN!!!!!!!!!!!!!!!!
Due Today
Due TodayTwo column notes save as a PDFWarm Up Log saved as a PDFCurrent EventVideo watched with commentInterpreting the Periodic Table
PeriodsPeriods run horizontally across the
Periodic TablePeriods are numbered 1–7All 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 ContinuedMoving 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…..
EarthFireWater 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
1649Made the first scientific
discovery of an element
PhosphorusHe isolated from urine,
a white, waxy material and named it phosphorus (“light bearer”), because it glowed in the dark.
A.E. Beguyer de Chancourtois
1817Listed 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
1863Classified 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 yet-to-be-discovered elements including eke-silicon and eke-boron
Lord Rayleigh
1895Discovered 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
1911Studied 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 TableGo to this website and look at the
different periodic tables for the rest of class
http://www.meta-synthesis.com/webbook/35_pt/pt_database.php?Button=pre-1900+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 PatternsNumber 1-5 and leave 3 lines between
each number
Periodic Trends
What does periodic mean? Recurring at regular intervals
What does trend mean? A pattern of gradual change or movement
What might be a good definition for periodic trends?
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?
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
The following elements all belong to the same period: Ne, Ar, Kr, and Xe. Disagree because they all have different numbers of
energy levels. 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. 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 UpAgree or Disagree and Why
Warm Up
Study your spiralWrite “Test” on your warm up log
After the Test
Turn in your spiral on lab table 2STAY QUEITYou may read, work on homework, or
log on to study island If we have time I will check your
grades after the test