Transcript File
AP Chemistry
Unit 3 - Elements
Lesson 10 – Electron
Configurations
Book Section: 6.4-6.9
Electron Configurations
This shows the
distribution of all
electrons in an atom.
Each component
consists of
A number denoting the
energy level;
Electron Configurations
This shows the
distribution of all
electrons in an atom.
Each component
consists of
A number denoting the
energy level,
A letter denoting the
type of orbital,
Electron Configurations
This shows the
distribution of all
electrons in an atom.
Each component
consists of
A number denoting the
energy level,
A letter denoting the
type of orbital,
A superscript denoting
the number of electrons
in those orbitals.
Aufbau Principle
The order in which
orbitals are filled with
electrons is known as
the Aufbau principle.
Full vs. Noble Gas
Configuration
You can use a noble
gas shell to shorten
electron
configurations.
Ex: Sodium
1s22s22p63s1
[Ne]3s1
Periodic Table
We fill orbitals in
increasing order of
energy.
Different blocks on the
periodic table (shaded
in different colors
here) correspond to
different types of
orbitals.
Periodic Table
Some
irregularities
occur when there
are enough
electrons to halffill s and d orbitals
on a given row.
Periodic Table
For instance, the
electron
configuration for
chromium is
[Ar]4s13d5 rather
than the expected
[Ar]4s23d4.
Copper is
[Ar]4s13d10.
Ionizing Transition Metals
When transition metals become ions, (Ex – Mn2+), the
electrons are lost first from the s block, rather than
the d block.
Electron configuration for Mn: [Ar]4s23d5
Electron configuration for Mn+2: [Ar]3d5
This is because the orbitals become “rearranged”
once the electrons are put in them. (Crystal Field
Theory & molecular orbitals – inorganic chemistry in
college)
AP 1989 MC #4-7
1s22s22p53s23p5
B)
1s22s22p63s23p6
C)
1s22s22p62d103s23p6
D)
1s22s22p63s23p63d5
E)
1s22s22p63s23p63d34s2
4) An impossible electron configuration
5) The ground-state configuration for the atoms of a transition
element
6) The ground-state configuration of a negative ion of a halogen
7) The ground-state configuration of a common ion of an alkaline
earth element
A)
AP 1989 MC #4-7
1s22s22p53s23p5
B)
1s22s22p63s23p6
C)
1s22s22p62d103s23p6
D)
1s22s22p63s23p63d5
E)
1s22s22p63s23p63d34s2
4) An impossible electron configuration – C (79% correct) - easy
5) The ground-state configuration for the atoms of a transition
element – E (42% correct) - medium
6) The ground-state configuration of a negative ion of a halogen – B
(62% correct) - easy
7) The ground-state configuration of a common ion of an alkaline
earth element – B (40% correct) - medium
A)
AP 1984 MC #22
1s22s22p63s23p3
Atoms of an element, X, have the electronic
configuration shown above. The compound
most likely formed with magnesium, Mg, is
MgX
Mg2X
MgX2
MgX3
Mg3X2
AP 1984 MC #22
1s22s22p63s23p3
Atoms of an element, X, have the electronic
configuration shown above. The compound
most likely formed with magnesium, Mg, is
MgX
Mg2X
MgX2
MgX3
Mg3X2 - 80% correct, very easy
AP 1984 MC #58
Which of the following represents the ground
state electron configuration for the Mn3+
ion? (Atomic number Mn = 25)
1s22s22p63s23p63d4
1s22s22p63s23p63d54s2
1s22s22p63s23p63d24s2
1s22s22p63s23p63d84s2
1s22s22p63s23p63d34s1
AP 1984 MC #58
Which of the following represents the ground
state electron configuration for the Mn3+
ion? (Atomic number Mn = 25)
1s22s22p63s23p63d4 – 32% correct - hard
1s22s22p63s23p63d54s2
1s22s22p63s23p63d24s2
1s22s22p63s23p63d84s2
1s22s22p63s23p63d34s1
HW: 6.48, 50, 52, 54, 56, 58
This Week:
Thursday – Gravimetric Analysis of a Chloride
Salt, Quantitative Analysis of Soluble Sulfate
Due
Friday – Electron Configurations (6.4-6.9)
10/18 – Gravimetric Analysis of a Chloride
Salt Due
10/20 – Elements Exam
10/21 – Problem Set 2 Due