Transcript Electron Configuration

Welcome to Day 31! September
3x101, 2009
Objectives changed last minute
SWBAT Draw orbital diagrams
SWBAT show electrons using electron configuration
Catalyst
(1) Pick up a chemistry book from the back or under your
chair and turn to pg. 137. Look at figure 5-18, that is the
quantum mechanical model for a Neon atom.
(2) What data did Rutherford discover and how did this data
change the model of the atom?
(3) Draw a Bohr model for the following elements:
(a)
Beryllium
Agenda
Catalyst Review 15min
Orbital Diagrams 15min
Practice 10min
Electron Configuration Notation
10min
 Practice! 20min
 Exit ticket 10min
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ANNOUNCEMENTS
 Quiz This Friday
 Unit 2 Test next Friday
Orbital Diagrams and
Electron Configuration
Notation
Ch. 5, sections 2 and 3
Orbital Diagrams & Electron Configuration
We need ways to keep
track of where electrons
are located in an atom
Orbital Diagrams & Electron Configuration
•Bohr Models
•Orbital Diagrams
•Electron configuration
BOHR MODEL
 Electrons orbit nucleus in defined,
circular orbits.
QUANTUM MECHANICAL MODEL
Electrons reside in:
 LEVEL (like the Bohr model)
 Ex. 1, 2, 3, 4, ...
 Within a level, they reside in a
SUBLEVEL
 Ex. s, p, d, f
 Within a sublevel, they reside in an
ORBITAL
 Ex. Fig 5-18
s and p Orbitals
III. Quantum Mechanical Model: Atomic Orbitals
E. Shapes of orbitals
d orbitals
Electron Configuration & Bohr Models
There are 4 orbitals:
some
pirates
die
fiercely
Four Sub-Energy Levels
Sub Level
(Type of
orbital)
Shape
# of
Orbitals
Max # of
electrons
s
Sphere
1
2
p
Dumbbell
(peanut)
3
6
d
4-Lobed
(doublepeanut)
5
10
f
6-8 Lobed
(flower)
7
14
How do we arrange electrons in
an atom?
 electrons in an atom want to
assume the arrangement with
the lowest energy; the lower
the energy, the more stable
the arrangement.
What rules do electrons follow?
(1)Aufbau Principle:
Electrons fill the lowest energy sublevels
first.
2) Pauli Exclusion Principle
 Electrons within an orbital must have
opposite spins.
 An arrow pointing up (↑) represents an
electron spinning one direction
 An arrow pointing down (↓) represents
an electron spinning in the opposite
direction
3) Hund’s Rule
Every orbital in a sublevel
is singly occupied with
one electron before any
one orbital is doubly
occupied.
2p orbital
Orbital Box Diagram
Example: Zinc
START
Atomic # =
# of electrons =
Example: Argon
START
Atomic # =
# of electrons =
Example: Calcium
START
Atomic # =
# of electrons =
Electron Configuration
 Electron configuration is a way of
writing out how electrons are
arranged.
Electron Configuration
Symbols
3
5f
Energy Level
e in
# of
sub-energy
level
Sub-Energy
Level
Electron configuration:
 Go back to Zn, Ar, and Ca
Practice with Whiteboards
Orbital diagram and electron
configuration for:
 Phosphorus.
Periodic Table Trick
Individual Practice
Please draw the orbital box diagram and write
the electron configuration for the following
elements:
(1)Boron
(2)Lithium
(3)Silicon
(4)Sodium
(5)Titanium
(6)Iron
(7)Selenium
(8)Galium
Homework
 Draw the orbital box diagram and
electron configuration for the following
elements:
(1)Beryllium
(2)Aluminum
(3)Argon
(4)Vanadium
 Memorize the names and symbols of
the 1st 20 elements on the periodic
table
Exit Slip #1
(1) Write the electron configuration for
Sulfur.