the periodic table by leonard calvin eds. how was the periodic table created? science is the search...
TRANSCRIPT
The Periodic Table
By Leonard Calvin EdS
How was the Periodic Table created?Science is the search for
patterns in nature.In the 1800’s, many
scientists noticed patterns in the properties of different elements.
Look at the following elements, what patterns do you notice?Element Atomic # Atomic Radius
IonizationH 1 37 1300He 2 50 2380
Li 3 152 520Be 4 111 900B 5 88 800C 6 77 1100N 7 70 1400
Na 11 186 480Mg 12 160 700Al 13 143 600Si 14 117 800P 15 110 1010
Who discovered the patterns?
Dimitri Mendeleev Introduced a chart
summarizing the known properties of the elements to his students.
The chart resembles a calendar.
What did the original Periodic Table look like? Arranged the
original 60 elements in order by their increasing masses.
Left blanks because he predicted there were missing elements.
Ponder this:
Was the great organization of the periodic table invented by humans or discovered by humans? Explain.
What does the modern periodic table look like?
How is the PTE arranged?
by the type of element (substance)by the state of the element (solid, liquid,
or gas).the mass of the element.
How is the PTE organized?
GROUPS Vertical columns Similar properties
among the elements Have the same # of
electrons in outer shell (valence electrons)
Group 1-used in the making of soaps
Group 2-fire resistant
Group 11-precious metals
Group 17-tendency to form salts
Group 18-unreactive gases
More on how the PT is organized: PERIODS Horizontal rows Same number of
energy shells (where the electrons are)
Example: Period 2Li Be B C NO F and NeAll have 2 energy shells
Quick Review!
The PTE is an arrangement of the __________.
The elements are arranged in increasing _________& ___________.
The PTE has columns called________.
The PTE has rows called___________.
More review!
Groups Vertical ________on
the PTE. Have __________
properties because of the same number of __________ in the outer shell.
Those are called v_______ electrons
Periods Horizontal _______
on the PTE. All elements in the
same row have the same # of
e______ s______.
What’s in the rectangles?
Atomic Number-the number of electrons or protons
Symbol
Name
Atomic mass-protons plus neutrons
Practice reading the Periodic Table: What is the atomic
number? 8 What is the symbol? O What is the name of the
element? oxygen What is the atomic
mass? 15.99
Practice reading the Periodic Table? What is the atomic
number? 79 What is the symbol? Au What is the name of the
element? gold What is the atomic
mass? 196.97
Practice finding the # of electrons, protons and neutrons. How many protons? 11 How many
electrons? 11 How many
neutrons? 22.98 -11.00 11.98
Practice finding the # of electrons, protons and neutrons. How many protons? 8 How many
electrons? 8 How many
neutrons? 15.99 - 8.00 7.99
Practice finding the # of electrons, protons and neutrons. How many protons? 79 How many electrons? 79 How many neutrons? 196.97 - 79.00 117.97
How do you use the Periodic Table? From the
information on the periodic table, we can find the number of electrons, protons and neutrons.
Atomic number equals the protons or electrons.
Atomic mass minus the atomic number equals the number of neutrons.
Another way the periodic table is organized:
MetalsNon-MetalsMetalloids
Metals 85% of known elements Shiny Opaque Good conductors of
electricity Good conductors of heat Malleable-can be molded Ductile-can be drawn into
wires All but a few are solid at
room temperature (ex: Mercury)
Located to the left of zig zag
Neodymium
Non-Metals
On the right side of the zig zag line.
Dull Non-conductors of
heat & electricity Brittle, will shatter
when hammered At room temperature
some are solid, some are liquid, some are a gas
Reactive solids
Carbon
Metalloids
Between metals and non-metals, along zig zag line
Weak conductors of heat and electricity
Used for semi conductors (conducts w/ higher temps)
Take on the properties of their group
If closer to the metals-have more metal properties
If closer to non-metals-take on those properties
Germanium
Boron
Metal, non-metal or metalloid?
Leah has an element that is silvery gray, solid, brittle and is a semi conductor.
What is it?
Metal, non-metal or metalloid?
Tommy has an element that is shiny, solid, can be pulled into wire(ductile) and is a good conductor of heat and electricity.
What is it?
Metal, non-metal or metalloid?
Michael has an element that is a yellow solid that crumbles and does not conduct heat or electricity.
What is it?