3.05 Atomic Structure and Electronic Configuration January 10 1
9.03 Atomic Structure and Electronic Configuration
Dr. F. O. Garces Chemistry 152 Miramar College
Learning Objectives/Terminology- Aufbau Hund’s Rule Pauli Exclusion Principle Diamagnetism/Paramagnetism Ne-Va-S-P
Arranging the electrons in an atom
3.05 Atomic Structure and Electronic Configuration January 10 2
Electronic Configuration How are the electrons of an atom arranged in the atom?
What are shells and orbitals arrange outside the nuclei of an atom?
How is the e- arrangement liken to that of a Hotel room (Hotel del Orbital) ?
What is the importance of the valence electrons and how do these influence chemistry?
3.05 Atomic Structure and Electronic Configuration January 10 3
PreLude to eConfiguration Placing electrons in orbitals to complete the electron configuration.
3.05 Atomic Structure and Electronic Configuration January 10 5
Relative Energies for Shells and Orbitals
1
2
3
4
567∞8
s p d f
Relative Energies of the orbitals
3.05 Atomic Structure and Electronic Configuration January 10 6
Hotel del Orbitals
s p d f
1
2
3
4
Filling Order (Aufbau Principle)
Like the hotel del Orbital, the shells of an atom are staggered and are filled based on their relative energies
3.05 Atomic Structure and Electronic Configuration January 10 7
Hotel del Orbitals and a pictorial view of the shell arrangements
The filling order can be memorized by the following scheme
1
2
3
4
3.05 Atomic Structure and Electronic Configuration January 10 8
2s • H = 1s1
• He = 1s2
• Li = 1s2 2s1
• Be = 1s2 2s2
• B = 1s2 2s2 2p1
• C = 1s2 2s2 2p2
• N = 1s2 2s2 2p3
• O = 1s2 2s2 2p4
• F = 1s2 2s2 2p5
• Ne = 1s2 2s2 2p6
1s
The First 10 elements:
2p
+ +
3.05 Atomic Structure and Electronic Configuration January 10 9
Electron Configuration Hydrogen and Helium
H
HeHe = 1s2
H = 1s1
1s 2s 2p
1s 2s 2p
Pauli Exclusion Principle
3.05 Atomic Structure and Electronic Configuration January 10 10
Relative Energies for Shells and Orbitals
1
2
3
4
567∞8
s p d f
Relative Energies of the orbitals
3.05 Atomic Structure and Electronic Configuration January 10 11
Electron Configuration: Lithium to Beryllium
Be
+ +
=
Li+ +
=
Li = 1s2 2s1
Be = 1s2 2s21s 2s 2p
1s 2s 2p
Aufbau Process
3.05 Atomic Structure and Electronic Configuration January 10 12
Relative Energies for Shells and Orbitals
1
2
3
4
567∞8
s p d f
Relative Energies of the orbitals
3.05 Atomic Structure and Electronic Configuration January 10 13
Electron Configuration: Boron to Nitrogen
N
+ +
=
C
+ +
=
B
+ +
=
B = 1s2 2s2 2p1
N = 1s2 2s2 2p3
1s 2s 2p
1s 2s 2p
1s 2s 2p
C = 1s2 2s2 2p2 Hund’s Rule
Paramagnetic
3.05 Atomic Structure and Electronic Configuration January 10 14
Relative Energies for Shells and Orbitals
1
2
3
4
567∞8
s p d f
Relative Energies of the orbitals
3.05 Atomic Structure and Electronic Configuration January 10 15
Electron Config: Oxygen to Neon
O
+ +
=
F
+ +
=
Ne
+ +
=
F = 1s2 2s2 2p5
Ne = 1s2 2s2 2p6
1s 2s 2p
1s 2s 2p
1s 2s 2p
O = 1s2 2s2 2p4
Diamagnetic
3.05 Atomic Structure and Electronic Configuration January 10 16
Relative Energies for Shells and Orbitals
1
2
3
4
567∞8
s p d f
Relative Energies of the orbitals
3.05 Atomic Structure and Electronic Configuration January 10 17
Electron Configuration using the Periodic Table
When using the Periodic table to determine the electron
configuration of an atom, it is important to understand the
layout of the periodic table.
The row of a periodic table can be used to determine which
energy level, 1, 2, 3... the valence electrons are located. The
column of the periodic table helps determine how many valence
electron an atom possesses. Elements in the 1A column (family)
have one valence electron, in the IIA column, elements have two
valence electron, in the IIIA family, elements have three
valence electrons, and so on.
3.05 Atomic Structure and Electronic Configuration January 10 18
The elements designated in -block is where the very last electrons are found in the s-orbitals. Therefore the elements in portion of the periodic table is referred to as the s-block elements. The elements designated in -block is where the very last electrons are found in the p-orbitals. The elements found in this portion of the periodic table is referred to as the p-block elements. The same can be said about the -block and -block with the elements found in this portion of the periodic table referred to as the d-block (transition metals) and f-block (man-made) elements.
Electron Configuration using the Periodic Table
3.05 Atomic Structure and Electronic Configuration January 10 19
Electron Configuration: ne-va-s-p
e- config. for Sulfur ?
1IA
18VIIIA
1 2IIA
13IIIA
14IVA
15VA
16VIA
17VIIA
2
3 3IIIB
4IVB
5VB
6VIB
7VIIB
8 9VIIIB
10 11IB
12IIB
4
5
6
7
H 1s1
Li 2s1
Na 3s1
K 4s1
Rb 5s1
Cs 6s1
Fr 7s1
Be 2s2
Mg 3s2
Ca 4s2
Sr 5s2
Ba 6s2
Ra 7s2
Sc 3d1
Ti 3d2
V 3d3
Cr 4s13d5
Mn 3d5
Fe 3d6
Co 3d7
Ni 3d8
Zn 3d10
Cu 4s13d10
B 2p1
C 2p2
N 2p3
O 2p4
F 2p5
Ne 2p6
He 1s2
Al 3p1
Ga 4p1
In 5p1
Tl 6p1
Si 3p2
Ge 4p2
Sn 5p2
Pb 6p2
P 3p3
As 4p3
Sb 5p3
Bi 6p3
S 3p4
Se 4p4
Te 5p4
Po 6p4
Cl 3p5
Be 4p5
I 5p5
At 6p5
Ar 3p6
Kr 4p6
Xe 5p6
Rn 6p6
Y 4d1
La 5d1
Ac 6d1
Cd 4d10
Hg 5d10
Ag 5s14d10
Au 6s15d10
Zr 4d2
Hf 5d2
Db 6d2
Nb 4d3
Ta 5d3
Jl 6d3
Mo 5s14d5
W 6s15d5
Rf 7s16d5
Tc 4d5
Re 5d5
Bh 6d5
Ru 4d6
Os 5d6
Hn 6d6
Rh 4d7
Ir 5d7
Mt 6d7
Ni 4d8
Ni 5d8
• ne - number of electrons; the total number of electrons • va - valence electrons; the number of valence electrons • s - shell of valence electrons • p - previous noble gas
3.05 Atomic Structure and Electronic Configuration January 10 20
Electron Configuration: Sulfur
p - previous noble gas
= Ne (10 e-)
ne - number of electrons; the total number of electrons; this equals the number of protons or atomic number = 16
Va - valence electrons; the number of valence electrons = 6
s - shell of valence electrons = 3
1IA
18VIIIA
1 2IIA
13IIIA
14IVA
15VA
16VIA
17VIIA
2
3 3IIIB
4IVB
5VB
6VIB
7VIIB
8 9VIIIB
10 11IB
12IIB
4
5
6
7
H 1s1
Li 2s1
Na 3s1
K 4s1
Rb 5s1
Cs 6s1
Fr 7s1
Be 2s2
Mg 3s2
Ca 4s2
Sr 5s2
Ba 6s2
Ra 7s2
Sc 3d1
Ti 3d2
V 3d3
Cr 4s13d5
Mn 3d5
Fe 3d6
Co 3d7
Ni 3d8
Zn 3d10
Cu 4s13d10
B 2p1
C 2p2
N 2p3
O 2p4
F 2p5
Ne 2p6
He 1s2
Al 3p1
Ga 4p1
In 5p1
Tl 6p1
Si 3p2
Ge 4p2
Sn 5p2
Pb 6p2
P 3p3
As 4p3
Sb 5p3
Bi 6p3
S 3p4
Se 4p4
Te 5p4
Po 6p4
Cl 3p5
Be 4p5
I 5p5
At 6p5
Ar 3p6
Kr 4p6
Xe 5p6
Rn 6p6
Y 4d1
La 5d1
Ac 6d1
Cd 4d10
Hg 5d10
Ag 5s14d10
Au 6s15d10
Zr 4d2
Hf 5d2
Db 6d2
Nb 4d3
Ta 5d3
Jl 6d3
Mo 5s14d5
W 6s15d5
Rf 7s16d5
Tc 4d5
Re 5d5
Bh 6d5
Ru 4d6
Os 5d6
Hn 6d6
Rh 4d7
Ir 5d7
Mt 6d7
Ni 4d8
Ni 5d8
S
Ne
e- config for Sulfur S = [Ne]3s23p4
• ne - number of electrons; the total number of electrons • va - valence electrons; the number of valence electrons • s - shell of valence electrons • p - previous noble gas
3.05 Atomic Structure and Electronic Configuration January 10 21 1
2
3
4
567∞8
Relative Energies of the orbitals and the filling order.
Electron arrangement for the Sulfur atom The 16 electrons for sulfur occupy the shells & orbitals of sulfur from the lowest energy to the highest.
s p d f
S
16 total electrons
e- config for Sulfur S = [Ne] 3s2 3p4
3.05 Atomic Structure and Electronic Configuration January 10 22 1
2
3
4
567∞8
Relative Energies of the orbitals and the filling order.
Electron arrangement for the Scandium atom The 16 electrons for sulfur occupy the shells & orbitals of sulfur from the lowest energy to the highest.
s p d f
21 total electrons
e- config for Scandium Sc = [Ar]4s23d1
Sc
3.05 Atomic Structure and Electronic Configuration January 10 23 1
2
3
4
567∞8
Relative Energies of the orbitals and the filling order.
Electron arrangement for the Scandium atom The 16 electrons for sulfur occupy the shells & orbitals of sulfur from the lowest energy to the highest.
s p d f
Sn
50 total electrons
e- config for Tin Sn = [Kr]5s24d105p2
3.05 Atomic Structure and Electronic Configuration January 10 24
The First 20 elements:
2s • H = 1s1
• He = 1s2
• Li = 1s2 2s1
• Be = 1s2 2s2
• B = 1s2 2s2 2p1
• C = 1s2 2s2 2p2
• N = 1s2 2s2 2p3
• O = 1s2 2s2 2p4
• F = 1s2 2s2 2p5
• Ne = 1s2 2s22p6
• Na = 1s2 2s22p63s1
• Mg = 1s2 2s22p63s2
• Al = 1s2 2s22p63s23p1
• Si = 1s2 2s22p63s23p2
• P = 1s2 2s22p63 s23p1
• S = 1s2 2s2 2p63s23p4
• Cl = 1s2 2s2 2p63s2 3p5
• Ar = 1s2 2s2 2p6 3s2 3p6
1s
2p
+ +
+ +
3p
3s
3.05 Atomic Structure and Electronic Configuration January 10 25
Assignment: Determine the electron configuration.
1. Write out the electron configurations for the following atoms and ions. Determine the number of unpaired electrons in the ground state. 13Al 12Mg+2 50Sn 15P-3 34Se-1 32Ge+2
2. Write the electron box diagram for the following elements.
Which have identical electron configuration (isoelectronic) ? S-2 Cl Ar Ca+2
3. What does the term: Aufbau, Pauli Exclusion and Hund’s Rule mean? 4. How does atomic radius change as one goes left to right along the periodic table?
Explain*. 5. How does the ionization change as one goes down the periodic table? Explain*.
* Explain, means explain why.
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