Q: What weapon can you make from the elements potassium,
nickel and iron?
A KNiFe.
Q: What do you get when you mix sulfur, tungsten, and silver?
SWAG
Q: Why can you never trust atoms?
They make up everything!
Q: What did the bartender say when oxygen, hydrogen, sulfur,
sodium, and phosphorous walked into his bar?
OH SNaP!
http://www.youtube.com/watch?v=cAnOUwPfHlk (Element
Rap) OR http://www.youtube.com/watch?v=lDp9hUf_SV8 (Pe
riodic Table Rap)
 Developed the first
real periodic table
which ours is based
upon.
 He was able to predict
the missing elements
and their properties
once the table was
put together.
MENDEELEV WAS A GENIUS!
Many of his predictions came true, such as the existence of
“eka-aluminum” which we know as gallium.
A missing element in his table made him believe that an
element with certain properties belonged there.
By looking specifically for this missing
“eka-aluminum”,
chemists were able to discover gallium.
His predictions were quite close to the actual values of the
various properties he quoted, such as mass, density, ionic
formula, and others.
 Elements that have similar properties
Chemical properties like:
fizzing in acid, exploding,
rusting, burning
Physical properties like:
color, luster, hardness,
texture, dissolves in water,
melting point, boiling point,
state (solid/liquid/gas)
density
1
 Put a box around the group numbers
 Be sure to label what the box means!
18
13
2
3
4
5
6
7
8
9
10
11
12
14
15
16
17
Tells the number of energy levels, or
electron shells, the atom has.
Atoms in the same period do NOT always
have similar chemical properties.
 A period usually has metals, nonmetals, and metaloids: all very different!
Put a circle around the period
18
1
1
2
3
4
5
6
7
13
2
3
4
5 6
7
8 9
10
11
12
14
15
16
17
 Elements in the middle and left of the table (except
Hydrogen)
 Most are shiny, solids
 Good conductors of heat and electricity
 Generally have high melting and boiling points
 Loses electrons
 Shiny luster
 Ductile-pull into a wire
 Malleable
*Hit with a mallet, does not break (Foil)
 Elements to the upper right, above the diagonal line
 More than half exists as gas
 Poor conductors of heat and electricity
 Generally have low melting and boiling points
 Brittle *Hit with a mallet, it will shatter (Glass, plastic)
 Dull luster
 Not ductile
 Gains electrons
 Elements near the stair stepped line
 Show characteristics of both metals and nonmetals
 Along zig zag line: B Si Ge As Sb Te Po At
Find the zig-zag line on the right
side of the table. Make it
DARKER.
Metals are on the left, nonmetals
on the right
Exception: Hydrogen is a
nonmetal
Color the Metals Yellow
Color the Nonmetals Green
Color the Metalloids
Purple
1
1
2
3
4
5
6
7
2
3
4
5 6
13
7
8 9
10
11
12
18
14
15
16
17
TRENDS IN THE PERIODIC
TABLE
A trend is a pattern
or a repetition of
particular properties.
BECAUSE OF SPECIFIC PROPERTIES...
our Periodic Table has a non-regular shape.
The elements are arranged by properties rather than a
way just make the table be uniform in shape.
The periodic table
is arranged
in a certain way
to keep elements with
similar properties close
together
THERE ARE
SEVERAL BASIC TRENDS
(or patterns)
THAT WE NEED TO
RECOGNIZE AND
UNDERSTAND.
What are some patterns we have already discussed?
Groups and Periods
Metals, Non-metals, Metalloids
Atomic Number
More patterns that are not so obvious..
1. Atomic Mass
(in amu)
2. Atomic Size
3. Net Nuclear Charge
4. Electronegativity (Reactivity)
OUR FIRST TREND
Atomic Mass
Atomic mass goes higher from element to element, with few
exceptions.
The Group Trend is that
atomic mass increases.
The Period Trend is that
atomic mass increases too.
OUR SECOND TREND
Atom Size
The Group Trend for atom
size is that it increases
down a group.
The Period Trend for atom
size is that it decreases left
to right.
Period Trend for Atomic Radius
Li
2-1
Be
2-2
B
2-3
•
•
•
C
2-4
N
2-5
O
2-6
F
2-7
Ne
2-8
• •
•
•
•
Atoms get smaller as you go across a period.
They gain electrons in the same energy levels, not getting bigger.
The additional positive charge from the additional protons pulls the
electron orbital slightly tighter for each atom going across the period.
SHOWS ATOMIC SIZES
FOR GROUPS AND PERIODS
Each atom is neutral because it has the SAME number of protons &
electrons.
Electrons fly around outside the nucleus in orbitals. Protons hang tight
(no joke) with the neutrons in the nucleus. Since the neutrons are neutral
(hence their name!), the only charge particles in the nucleus are the protons,
which are ALL POSITIVE. So, the NET NUCLEAR CHARGE is how many
protons are there in the nucleus, and since each is positively charged, that is
the answer.
Example: Mercury is number 80, with 80 electrons and 80 protons, a neutral
atom. It also has 121 neutral neutrons in the nucleus with the 80 protons.
So, NET nuclear charge = +80.
ELECTRO-NEGATIVITY
SIMILAR TO REACTIVITY
the measure of the attraction an
atom has to gain an electron
in a chemical reaction.
Fluorine has the greatest desire of all atoms
for that electron gain. Fluorine is given the
rating of 4.0 on the E-N scale, the highest
Electronegativity of all elements.
 Fluorine tops out the scale
at 4.0
 Pauling set this standard,
because he could.
 It’s a totally arbitrary
scale, based upon Fluorine
and at 4.0 just because.
All other atoms are
compared to that one.
 All the other electro-
negativity values are
relative to Fluorine’s
 Going down
a group the
trend is towards
LOWER E-N
values.
Going across a
period the trend is
towards higher EN values.
It is all about HOW CLOSE IS THE ATOM TO FLUORINE
which determines the relative electro-negativity.
REMEMBER…
Trends are just trends,
they do not ALWAYS hold true.