Catalyst – February 12-5+4, 2010
1.
2.
3.
4.
How did Rutherford add to
Thompson’s theory?
Draw the Bohr model of Chlorine.
How many electrons can fit into d
orbitals?
How many electrons fit in the 2nd
energy level?
Catalyst
These are the electron configurations for the
following elements:
2 2
6 2
 Mg-1s 2s 2p 3s
2 2
6
 Ne- 1s 2s 2p
2 2
6 2
2
 Si- 1s 2s 2p 3s 3p
2 2
6 2
6 1
 K- 1s 2s 2p 3s 3p 4s
 Find the electron configuration of:
1.
2.
Fe
O
Today’s Agenda
Catalyst
 Continue Electron Configuration
 Practice!
 Review (time left after EC)
 Exit Question

Today’s Objectives
SWBAT write electron
configurations for elements.
 SWBAT write noble gas
configurations for elements.

Electron Configuration Review
Fill in the table below on your notes.
Orbital Type
(s, p, d, or f)
s
p
Energy Level
1,2,3,4…
# of Orbitals
1
Maximum #
of Electrons
2
2,3,4…
3
6
d
3,4…
5
10
f
4…
7
14
Electron Configuration
Key Point #3: Electron configuration
shows how the electrons are
distributed among the various
atomic orbitals and energy levels.
 The format consists of a series of
numbers, letters, and superscripts as
shown below:

1s2
Electron Configuration
2
1s
Large number = energy level
 Letter = atomic orbital
 Superscript (small) number =
number of electrons in atomic
orbital

Figure it out yourself!! (15 mins)

Look at the tables that have 1s, 2s, 2p on your notes sheet.
Below, I have shown 4 correct electron configurations. See if
you can figure out how to do the last two.
Mg -1s22s22p63s2
2 2
6
 Ne - 1s 2s 2p
2 2
6 2
2
 Si - 1s 2s 2p 3s 3p
2 2
6 2
6 1
 K - 1s 2s 2p 3s 3p 4s
S B 
Before we move on…
Let’s relate this to good ole
Bohr Models
Hydrogen
Helium
Lithium

Subshells on the Periodic Table
s
p
d
f
N–
Electron Configuration
2
1s
N–
Electron Configuration
2
2
1s 2s
N–
Electron Configuration
2
2
3
1s 2s 2p
N–
Electron Configuration
2
2
3
1s 2s 2p
= 7 e-
Na –
Electron Configuration
2
1s
Na –
Electron Configuration
2
2
1s 2s
Na –
Electron Configuration
2
2
6
1s 2s 2p
Na –
Electron Configuration
2
2
6
1
1s 2s 2p 3s
= 11 e-
Electron Configuration
Try these on your own!
Be:
Ne:
Br:
Electron Configuration
Be:
2
2
1s 2s
Ne:
2
2
6
1s 2s 2p
Br: 1s22s22p63s23p64s23d104p5
Work Time
Please complete the
Independent Practice Problems
Part One in your notes
If you finish early, get an
extra credit practice sheet
from Mr. Jhaveri

Electron Configuration
Scientists are WAY too
lazy to write all that
mess!
Electron Configuration
FIGURE IT OUT YOURSELF!!! (10 mins)
2
9
[Kr]5s 4d
Ag –
2
4
S – [Ne]3s 3p
2
2
Sm – [Ar]4s 3d
SiRb-
Electron Configuration
Noble Gas Configuration –
simply start writing your
notation from the last noble
gas BEFORE the atom you are
going to.
Ag
Electron Configuration
Ag –
Electron Configuration
2
9
[Kr]5s 4d
Electron Configuration
Ca
Ca
Electron Configuration
2
– [Ar]4s
Electron Configuration
S
S–
Electron Configuration
2
4
[Ne]3s 3p
Electron Configuration and
Valence Electrons
Each group: Write long electron configurations for
first four elements in given family.
 Group 1: Alkali Metals (1)
 Group 2: Alkaline Earth Metals (2)
 Group 3: Boron’s group (13)
 Group 4: Nitrogen’s group (15)
 Group 5: Halogens (17)
 Group 6: Noble Gases (18)
Electron Configuration and
Valence Electrons
Each group: Write long electron configurations for
first four elements in given family.
 Group 1: Alkali Metals (1)
 Group 2: Alkaline Earth Metals (2)
 Group 3: Boron’s group (13)
 Group 4: Carbon’s group (14)
 Group 5: Nitrogen’s group (15)
 Group 6: Oxygen’s group (16)
 Group 7: Halogens (17)
 Group 8: Noble Gases (18)
Electron Configuration and
Valence Electrons
What trends do you see? How many valence
electrons are there in each group?
 Group 1: Alkali Metals (1)
 Group 2: Alkaline Earth Metals (2)
 Group 3: Boron’s group (13)
 Group 4: Nitrogen’s group (15)
 Group 5: Halogens (17)
 Group 6: Noble Gases (18)
Electron Configuration and
Valence Electrons
What trends do you see? How many valence
electrons are there in each group?
 Group 1: Alkali Metals (1)
 Group 2: Alkaline Earth Metals (2)
 Group 3: Boron’s group (13)
 Group 4: Carbon’s group (14)
 Group 5: Nitrogen’s group (15)
 Group 6: Oxygen’s group (16)
 Group 7: Halogens (17)
 Group 8: Noble Gases (18)
Valence Electron Trends
on the Periodic Table
Homework/Review Sheet

GAMEDAY TOMORROW!!
Exit Question
Write the noble gas
configuration for

Bromine
Copper
Sodium
Exit Question