1. PERIODIC TABLE
&
PERIODIC TRENDS
Organize the following classes into categories.
Chemistry 101 Marketing 214 Art 323
Music 211 Physics 404 Speech 105
Calligraphy 324 Biology 324 Phys Ed 010
Astronomy 212 Economics 103 Sculpture 102
Writing 462 Finance 321 Poetry 209
English 104 Phys. Ed 005 Business 412

3. Where did the Periodic Table
come from?
• 1829
– J.W. Dobereiner
• Triad Classification
• 1864
– John Newlands
• Law of Octaves
• 1869
– Dmitri Mendeleev
• Credited with modern
Periodic Table

4. Still Not Perfect
Potassium
Atomic Mass: 39.10 amu
• Highly reactive Metal
Argon
Atomic Mass: 39.95 amu
• Inert gas
*Important fact you may want to right down*
The Modern Periodic Table is based on atomic
number and electron configuration, not atomic mass.

5. Periodic Law
• When elements are
arranged in order of
increasing atomic
number, there is a
periodic repetition
of their physical and
chemical properties.
Ya’ll best line up d’em elements in
order of increasing proton number
to pick out the properties!

6. METALS
• Have only a few
electrons in outer
most energy level.
• Lose e-
to form
positive ions (X+
)
• Good Conductors
• Malleable (sheets)
• Ductile (wire)
• Often Lusterous

7. NONMETALS
• More than 3 e-
in their
outermost orbit
• Gain electrons to form
negative ions (X-
)
• Dull in appearance
• Brittle

8. METALLOIDS
• Have properties of metals & nonmetals
• Positioned on metal / nonmetal line
• B, Si, Ge, As, Sb, Te, Po, At

9. A Groups = Main Group Elements
ALKALI
ALKALINEEARTH
NOBLEGASES
HALOGENS
CHALCOGENS
IA IIA VIAVIIA VIIIA
IB – VIIIB
TRANSITION METALS
INNER TRANSITION METALS
(Lanthanide & Actinide Series)
VAIVAIIIA
3B 4B 5B 6B 7B 8B 1B 2B
Coinage Metals

10. Pick a Trend, Any Trend
1. Atomic Size
2. Ionization Energy
3. Electron Affinity
4. Electronegativity

11. Atomic Radius:
No definite shape, but scientist can get a rough
measure.

12. Atomic Size
It doesn’t depend on Weight Watchers

13. Ionization Energy
The energy required to remove
an electron from an atom in
the gas phase.
A(g)+ Energy  A+
(g) + e-
Ionization energy measures
how tightly an electron is
held in the atom.

14. Ionization Energy (cont.)
• More and more energy is required to move
each electron from an atom
• Metals generally have low IE.
• Nonmetals have high IE.
• IE increases as you move across a period
and decreases as you go down a group or
family.

15. Electron Affinity
EA – It’s NOT a clothing company
• The energy used or released for a
gaseous atom to gain an electron.
A(g) + e-
 A-
(g) + Energy

16. Electron Affinity (cont.)
In general. . .
• EA increases (becomes more negative) as you go across a
period and decreases as you go down a group or family.
• The greater the electron affinity, the greater the IE.
– Metals have lower EAs
– Nonmetals have higher EAs

17. Electronegativity
A comparative scale relating the abilities of
elements to attract electrons when their
atoms are combined.
• Active metals (IA) have the lowest Ens
• Most nonmetals have the highest Ens

19. And Now a guest appearance by
Mr. Tom Lehrer