Chemistry – Nov 14, 2016
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
P3 Challenge
Which is smaller? N or P
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Which is larger? K+ or K

Which has the higher ionization energy? K or Br

Which has the higher electronegativity? O or Br
Get out Periodic Trends
Worksheet for Hmk Check
Objective –

Quantum Mechanics / Atomic Structure (Get out your colored periodic table)
Chemistry – Nov 14, 2016

Objective –



Atomic Structure / Quantum Mechanics
Agenda

Homework Review

Bohr model review, QM overview

Orbital Shapes

Organization of orbitals

Filling order

2D images (given time)
Assignment: Quantum Numbers Worksheet
Homework Review

1.
O, C, Al, K

2.
Ne, Al, S, O (noble gases = 0)

3.
F is smaller atom, higher on PT, harder to remove electron from F than I

4.
same group

5.
a. decrease

6.
Atomic Radii increase going down PT, Re: more electrons repel each other

7.
Ionization E increase going L R, Re: same size, but Z is increasing.
b. increase
c. increase
Homework Review

8.
a. Al
Al is lower on PT
b. Na
same period, Al is
smaller due to higher Z
c. S
S is lower on PT
d. O
same period, O is larger
because it’s to the left
e. Br
Br lower on PT
f. Ca
Ca lower on PT

9.
a. Be
I.E increases L R
b. Ca
Ca is smaller
c. Na
Na is smaller
d. Ar
Ar noble gas, I.E increases L R
e. Cl
I.E increases L R
f. Li
Li is smaller
Homework Review

10.
a. Ga
Ga to the right
a. Ca
Cations get smaller
b. Br
Br to the right
b. Br–
anions get larger
c. O
O to the right
c. Na+
Isoelectronic, Na has lower Z
d. Sr
Sr is above Ba
d. Ba+2 Ba is below Sr
e. Cl
Cl is to the right
e. Cl–
isoelectronic, Cl has lower Z
f. O
O is above S
f. S–2
S is below O

11.
Bohr model and Quantum models

Recall the Bohr model that uses quantized orbits

Recall Quantum Mechanics that uses quantized orbitals

Orbitals that we draw represent a 90% probability of finding
an electron in that space.

Any single orbital can contain up to two electrons (0, 1, or 2)
Quantum Mechanics

Same as Bohr model except for how the energy levels are described.

Electrons located in orbitals.


Mathematical description is a “wave function” - Schrödinger

Explains the wave property of matter.
Strategy to understand QM:

Learn what the orbitals look like and how they’re organized on H atom

Populate the orbitals with electrons to describe other atoms
Shapes of Orbitals

The bigger an orbital, the higher the energy level

The more complicated the shape, the higher the energy level.

Using different shapes is how QM creates its quantized energy levels.

Four different basic orbital shapes: s p d f

Basic shapes double the number of lobes for each level:
P, D, and F Orbitals
Quantum Mechanics Atomic Model 
Electrons organized on 4 levels

1) Shells 1, 2, 3, 4, 5, 6, 7
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2) Subshells s, p, d, f
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3) Orbitals

4) An orbital can hold up to two electrons.

S subshells contain 1 orbital (room for 2 e)

P subshells contain 3 orbitals (6 e)
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D subshells contain 5 orbitals (10 e)

F subshells contain 7 orbitals (14 e)
•
•
•
•
•
•
•
•
Shell 1 – s (2e)
Shell 2 – s and p (8e)
Shell 3 – s and p and d (18e)
Shell 4 – s and p and d and f (32e)
Shell 5 – s and p and d and f (32e)
Shell 6 – s and p and d (18e)
Shell 7 – s and p (8e)
2 + 8 + 18 + 32 + 32 + 18 + 8 = 118
• Structure for all 118 known
elements.
Hydrogen Atom
Shell 1
Shell 2
1s
2s
2
2
Shell 3
2p
2
3s
2
3p
Shell 4
3d
2
2
2
2
2
2
4s
2
4p
Shell 5
4d
4f
5s
2
2
2
2
2
2
2
2
2
5p
Shell 6
5d
5f
6s
2
2
2
2
2
2
2
2
2
2
2
2
2
6d
7s
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
7p
2
2
2
6p
Shell 7
2
• Each small box with a 2 represents a single empty orbital that has a capacity of 2 electrons.
Quantum Numbers

Four Quantum Numbers used to describe the structure. Memory items.
Quantum
Number
n
Name
Allowed
Values
Determines
Specifies a
Common
labels
Principle
1, 2, 3, 4…..
Size and
Energy
Shell
1,2,3,4…
(Period #)
Angular
Momentum
0, 1, 2… (only
up to n-1)
Shape
Subshell
s, p, d, f
Orientation
Orbital
Subscripts (x,
y, z, xy, yz
etc…
Spin
Electron
Up ↑, Down ↓
ml
Magnetic
ms
Spin
  ml 
+½ or -½
How Electrons Fill the Orbitals – the rules

The orbitals are present on every atom, but only some have electrons located in them
depending on how many electrons the atom has.

Three guiding principles to use:

1) Aufbau Principle: Electrons live in the lowest energy orbitals possible. (Higher energy
orbitals remain empty.)

2) Hund’s Rule: Electrons would rather not live with another electron, but its better to be
paired up than to live at a higher energy. If paired, they have opposite spins.

3) Pauli Exclusion principle: No two electrons can occupy the same space. No two
electrons can have the same 4 quantum numbers
Orbital Energy Levels

Energy levels are not intuitive because the energy levels of the shells
overlap.
Hydrogen Atom

Order of filling:

1s…2s, 2p…3s, 3p….
1s
2s

Then the shells start to overlap.
2
2

…4s, 3d, 4p…5s, 4d, 5p…
Shell 1
Shell 2
Shell 3
2p
2
3s
3d
2
2
2
2
2
2

…6s, 4f, 5d, 6p…7s, 5f, 6d, 7p

If that seems hard to remember, try this…
2
3p
Shell 4
4s
2
4p
Shell 5
4d
4f
5s
2
2
2
2
2
2
2
2
2
5p
Shell 6
5d
5f
6s
2
2
2
2
2
2
2
2
2
2
2
2
2
6d
7s
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
7p
2
2
2
6p
Shell 7
2
• Shells 1-7
• Periods
• S block
• 1–2
• H = 1s
• P block
• 13-18
• B = 2p
• D block
• 3-12
• Sc = 3d
• F block
• Lanthanides
• Actinides
• La = 4f
*lanthanides
**actinides
Lanthanum
Cerium
57
58
La
138.91
Ce
140.12
Praseodymium
59
Pr
140.91
Neodymium
60
Nd
Promethium
Samarium
Europium
Gadolinium
Terbium
Dysprosium
Holmium
Erbium
Thulium
61
62
63
64
65
66
67
68
69
Gd
Tb
Dy
157.25
158.93
Pm
144.24
(145)
Sm
Eu
150.36
151.97
162.50
Ho
164.93
Er
167.26
Actinium
Thorium
Protactinium
Uranium
Neptunium
Plutonium
Americium
Curium
Berkelium
Californium
Einsteinium
Fermium
89
90
91
92
93
94
95
96
97
98
99
100
Ac
Th
Pa
U
Bk
Cf
Es
232.04
231.04
(247)
(251)
(252)
(227)
238.03
Np
(237)
Pu
(244)
Am
(243)
Cm
(247)
Fm
(257)
Tm
168.93
Mendelevium
101
Md
(258)
Ytterbium
70
Yb
173.04
Nobelium
102
No
(259)
s
p
d
f
1
1s
2
2s
2p
3
3s
3p
3d
4
4s
4p
4d
4f
5
5s
5p
5d
5f
6
6s
6p
6d
7
7s
7p
Exit Slip - Homework

Exit Slip:


What’s Due? (Pending assignments to complete.)


Determine the highest energy subshell for Strontium and Silicon
Quantum Numbers Worksheet
What’s Next? (How to prepare for the next day)

Read Holt p84 - 88