Transcript Oxygen - Hingham

Chapter 5
The Periodic Table
Dimitri Mendeleev
Mendeleev’s Proposal
Arranged the elements into rows in
order of increasing mass.
Elements with similar properties were
in the same column.
Mendeleev ‘s Predictions
Mendeleev predicted where new
elements would appear in the table.
Properties of new elements showed
how useful his periodic table could be.
Homework
5-1 Worksheet
Due: 11/5/08
Periodic Table
Arrangement of the elements:
 Chemical Properties
 Atomic Number
Number of Protons
Group
Vertical Column
Repeating
Chemical Properties
Increase Mass
Group 11-1B
Groups
Same number of
Valence Electrons
(Number of Electrons in the
Outer Energy Level!!)
Be
Group 2
Mg
Ca
Ba
Ra
Sr
Periods
Horizontal Rows
Same Number
of
Energy Levels
Period - 2
Li
Be
B
C
N
O
F
Ne
H - Hydrogen
C - Carbon
O - Oxygen
Fe - Iron (ferrum)
He - Helium
Cu - Copper (cuprum)
Hg - Mercury (hydragyrum)
Co - Cobalt
Unp - Unnilpentium
Names and Chemical Symbols
Same group - Same number of
electrons in their outer shells.
Group 1 (H) – 1eGroup 2 (Be) – 2eGroup 13 (B) – 3eGroup 14 (C) – 4eGroup 15 (N) – 5eGroup 16 (O) – 6eGroup 17 (F) – 7eGroup 18 (He) – 8e-
Atomic Number
(# of Protons)
Symbol
Average
Atomic Mass
(31)
Name
15
P
30.96376
Phosphorus
Atomic Mass Unit
Atomic mass unit is equal
to one-twelfth of the mass
of the nucleus of a
carbon-12 atom.
Atomic Mass Unit
Atomic Mass Unit
+
p
0
n
Proton: Atomic Mass – 1amu
Neutron: Atomic Mass – 1amu
Atomic Mass of 7 amu
Isotopes
Atoms of the same element
can have different
numbers of neutrons
.
Isotopes of Chlorine
17
Cl
35
17
Cl
37
17 Proton
18 Neutrons
76%
17 Proton
20 Neutrons
24%
Average Weighted Mass
of
Chlorine
35.453amu
Metalloids
Metals
NonMetals
Metals
75%
of the
Elements!!!
Metals
Physical Properties of Metals:
1. Metallic shine or luster.
2. Usually
solids at room
temperature.
Metals
3. Malleable
(Hammered, pounded, or pressed
into different shapes
without breaking.)
Metals
4. Ductile:
(Drawn into thin sheets or
wires without breaking.)
5. Good conductors of heat and
electricity.
Metals
Metals tend to give up e-.
Na
Most Reactive Metals
Fr
Li
Francium
Most Active Metal
Non-Metals
There
are 17 nonmetals.
They have four major
physical properties.
Non-Metals
Physical Properties
1. Rarely have metallic luster.
2. Usually gases at room temperature.
Non-Metals
3. Nonmetallic solids are neither
malleable nor ductile.
4. Poor conductors of heat and
electricity.
Non-Metals
Non-Metals tend to
gain e-.
Cl
Most Reactive Non-Metal
F
I
Fluorine
Most Active
Non-Metal
The
B
Si
Ge
As
Sb
Te
Po

Metalloids
seven metalloids are:
B
Si
Ge As
Sb Te
Po
Metalloid Properties
Characteristics
in between that of
the metals and the nonmetals.
Sometimes
they are good
conductors of heat and electricity.
Variations across a Period
Across a Period

Less Metallic more Non-Metallic
Homework
5-2 Worksheet
Due: 11/13/08
Valence Electrons
The electrons in the
highest occupied energy
level of an atom.
Valence Electrons
Elements in a group have
similar properties because
they have the same
number of valence
electrons..
Boron
Carbon
Nitrogen
Oxygen
Halogens
Noble Gases
Alkaline Earth Metals
Alkali Metals
Li
Na
K
Rb
Cs
Fr
Alkali Metal
 Group 1A
Very reactive metals.
 Do not occur freely in nature.
 Only one electron in their outer
shell. (1 valence Electron)
Most reactive metal!!!!
Alkaline Earth Metal
Be
 Group 2A
Mg

Ca
Sr
Ba
Ra
Very reactive
 Not found free in nature.
 Two electron in their outer shell.
(2 Valence Electron)
Magnesium and Calcium
important elements in life.
B
Al
Ga
In
Tl
Boron Family
 Group 3A
 Three electrons in their outer
shell.
(3 Valence Electrons)
Aluminum is the most abundant
metal in the Earth’s crust.
Carbon Family
C  Group 4A.
Four electrons in their outer shell.
Si
(4 Valence Electrons)
Ge  Consists of:
Sn



One nonmetal (carbon)
Two metals (tin and lead)
Two metalloids (silicon and germanium).
Pb  Except for water, most compounds in
your body contain carbon.
N
P
Nitrogen Family

Group 5A.
 Five electrons in the outermost
energy level.
As
(5 Valence Electrons)
Sb  They physical and chemical
properties that are strikingly
Bi different.
 N and P make up fertilizer.
O
S
Se
Te
Po
Oxygen Family
 Group 6A.
Six electrons in their outermost
energy level.
(6 Valence Electrons)
Oxygen is the most abundant
element in the earth’s crust.
F
Cl
Br
I
At
Halogens
 The
halogens are five non-metallic
elements found in group 7A of the
periodic table.
 All halogens have 7 electrons in
their outer shells.
 The halogens exist, at room
temperature, in all three states of
matter.
Noble Gases
He
 The six noble gases are found in
Ne group 8A of the periodic table.
 These
elements were considered to
Ar be inert gases.
Kr  All noble gases have the maximum
number of electrons possible in
Xe their outer shell (2 for Helium, 8
for all others), making them stable.
Rn  Colorless/Odorless Gases
Electron Dot Diagram
Lewis Diagram
Dot Diagram:
• Symbol of the element
• Dots for Valence Electrons.
(Outer most energy level Electrons)
C
Cl
Ne
Na
Homework
5-3: Worksheet
Due: 11/14/08
Word-Wise & Math
Due: 11/17/08
Test: 11/19/08
Test
11/20/07