1. The Periodic Table of Elements

3. Periodic  Periodic Table
Something periodic occurs at regular or at least generally predictable intervals
Periodic Table of Elements – a table of the elements, arranged by atomic number, that shows the patterns in their properties

4. Element
A pure substance made up of one kind of atom that cannot be broken down into simpler substances by physical or chemical means
94 occur naturally on earth
24 were synthesized (made) by scientists
Element Song

5. Dmitri Mendeleev
In the 1860’s he devised a periodic table where the elements were ordered by their atomic masses
He did this by grouping elements together according to their similarities
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6. Mendeleev’s Published Periodic Table of Elements
Why do you think there are question marks here?
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7. Mendeleev’s Predictions
Although Mendeleev’s Periodic Table of Elements had missing elements or “gaps,” he was able to predict the characteristics of these missing elements because of Periodic Law.
“Ekasilicon”
Germanium
Notice how Mendeleev’s
predictions (orange column) were very
accurate when compared to Germanium’s actual characteristics (green column)
Date Predicted
1871
Date Discovered
1886
Atomic Mass 72
72.6
Density
5.5 g/cm3
5.47 g/cm3
Bonding Power 4
Color
Dark Gray
Grayish White

8. Henry Moseley
In 1914, his work led to a revision of the periodic table by rearranging the elements by their atomic numbers (not atomic masses)
He concluded that the number of protons in an atom is its atomic number
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9. Energy Levels and their Names

10. 3 Classes of Elements
Using this as a guide, color code your periodic table to show the three classes. Start by highlighting the “zig-zag.”
Class
Color
Metal
Non-Metal
Metalloid

11. What metal is not a solid
Metals
Location
Found on the left of the zigzag line/staircase on the periodic table (exception  Hydrogen)
Chemical Properties
Have few electrons in their outer energy level, thus lose electrons easily
Physical Properties
Ductile (able to be drawn out into a thin wire), good conductors, malleable (able to be hammered without breaking or cracking), shiny, most are room temperature 79 Au 11 Na
22.990
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What metal is not a solid
@ room temperature?

12. Atoms with Few Electrons in their Outer Energy Level11 Na
22.990
Notice: only 1 electron in outer level + - + - 4 Be
9.012
Notice: only 2 electrons in outer level

13. Non-Metals
Location
Most found to the right of the zigzag line/staircase on the periodic table
Chemical Properties
Most have almost full outer energy levels, thus they tend to gain electrons; some have completely full outer level
Physical Properties
not ductile or malleable, not shiny, poor conductors, most are solid, but some are gas at room temperature 17 Cl
35.453
Image taken from: 16 S
32.066
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14. Atoms with Full or Almost Full Outer Energy Level+ - 8 O
15.999
    + -
Notice: 2 electrons in outer level – FULL 2 He
4.003 + -
Notice: 6 electrons in outer level – almost full
Notice: 7 electrons in outer level – almost full 9 F
18.998

15. Metalloids
Location
Border the zigzag line/staircase on the periodic table
Chemical Properties
Most atoms have ½ (≈) complete set of electrons in outer level
Physical Properties
have properties of both metals and non-metals 14 Si
28.086
Image taken from: 5 B
10.811
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16. Atoms with ½ (≈) Complete Outer Energy Level+ -
Notice: only 4 electrons in outer level
                    5 B
10.811 + -
Notice: only 3 electrons in outer level 14 Si
28.086

17. Important Features of the Periodic Table: Period (Row)
each horizontal row of elements on the periodic table
How many
periods (rows)
are on the
Periodic Table
Of Elements?
FROM LEFT TO RIGHT OR RIGHT TO LEFT

18. Period (Row) Properties
Seven periods on a periodic table (numbered from the top down)
Atomic numbers and atomic masses increase as you move from the left to the right in a period
All atoms of the elements in the same period have the same number of orbitals/levels
All atoms of the elements in a specific period have that respective number of orbitals/levels
Example
Period 1 = 1 orbital
Period 2 = 2 orbitals
Period 3 = 3 orbitals
Etc…

19. Periods Each row is called a “period”
Elements in each period have the same number of energy shells
Periods
1st Period = 1 Shell
2nd Period = 2 Shells
3rd Period = 3 Shells
4th Period = 4 Shells

20. Examples of Period (Row) elements having the same number of orbitals/levels in their atoms+ - + -
In what period (row) do
you think these atoms
reside? + - + -
In what period (row) do
you think these atoms
reside?

21. How many groups (families)
Important Features of the Periodic Table: Group (Family)
each column of elements on the periodic table
How many groups (families)
are on the
Periodic Table
Of Elements?
FROM TOP TO BOTTOM OR BOTTOM TO THE TOP

22. Group (Family) Properties
Eighteen groups on the periodic table (numbered from left to right)
Atomic numbers and atomic masses increase as you move from the top down in a group (family)
Atoms of elements in the same group have the same number of electrons in the outer orbital/levels of their atoms (known as valence electrons)
Exceptions:
Transition elements (3-12)
Hydrogen (has no neutron)
Helium (actually has 2 valence electrons)
Elements in groups usually have similar physical and chemical properties

23. Groups / Families Group 1 = 1 electron Group 2 = 2 electrons
3, 4, 5, 6, 7
Except for He,
it has 2 electrons
Each column is
called a “group”
Each element in a
group has the same
number of electrons
in their outer orbital,
also known as “shells”
The electrons in the
outer shell are called
“valence electrons”

24. Examples of Group Elements with the same # of valence electrons
                          
How many electrons do each of these atoms have in their outer orbital/level? 87 Fr
(223) 55 Cs 37 Rb
85.468 19 K
39.098 11 Na
22.990 3 Li
6.941 1 H
1.008 + -
What group (family) do these elements reside in?

25. Group (Family) Names Halogens Nitrogen Group Alkali Metals
Alkaline Earth Metals
Boron Group
Noble Gases
Carbon Group
Oxygen Group
Transition Metals

26. Transition Elements Transition Metals have slightly different rules
for shells and
valence electrons

27. Transition Elements
This is something you will learn about in High School Chemistry.
They are all metals which are harder than alkali metals and less reactive with water.
Their name denotes their central location on the periodic table.
Here you find some well known elements like iron, copper, nickel, silver and gold. Because some are noncorrosive they are used in implant devices.

28. Identify the Element Period 5 – Group 2  Group 4 – Period 7 
Rutherfordium - Rf
Strontium - Sr
Carbon - C
Astatine - At

29. Using the Periodic Table
The boxes that make up the periodic table contain a significant amount of information. To understand this information, it is necessary to refer to the periodic table’s key(s) 8 O
Oxygen
15.999
Atomic Number
(Number of protons)
Element Symbol
(Written with a capital letter or a capital followed by a lower case if two letters )
Element Name
Atomic Mass
(Rounded to a whole number, equals
the number of protons and neutrons)
Class
Color
Metal
Non-Metal
Metalloid
State
Room Temp.)
Symbol Color
Solid
Liquid
Gas
What is Oxygen’s physical state of matter?
Which class does Oxygen fall into?

30. Determine the number of shells and the number of valence electrons for:
Carbon - C
2nd Period = 2 shells
4th Group =
4 valence
electrons

31. Determine the number of shells and the number of valence electrons for:
Sodium - Na
3rd Period = 3 shells
1st Group =
1 valence
electron

32. Write your answers on your handout.Ne
Name the element.
Number of shells ?
Valence electrons ?

33. Write your answers on your handout.Ne
Neon
Name the element.
Number of shells ?
Valence electrons ?
2nd Period = 2 shells
8th Group = 8 valence
electrons

34. Write your answers on your handout.
Name the element.
Number of shells ?
Valence electrons ?

35. Write your answers on your handout.
Hydrogen
Name the element.
Number of shells ?
Valence electrons ?
1st Period = 1 shell
1st Group = 1 valence
electron