Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the...
-
Upload
chaim-goley -
Category
Documents
-
view
222 -
download
0
Transcript of Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the...
![Page 1: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/1.jpg)
Chapter 13Electrons in Atoms
![Page 2: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/2.jpg)
Section 13.1Models of the Atom
OBJECTIVES: Summarize the development of
atomic theory.
![Page 3: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/3.jpg)
Models of the AtomOBJECTIVES: Explain the significance of
quantized energies of electrons as they relate to the quantum mechanical model of the atom.
![Page 4: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/4.jpg)
Greek Idea Democritus and
Leucippus Matter is made up
of solid indivisible particles
John Dalton - one type of atom for each element
![Page 5: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/5.jpg)
J. J. Thomson’s Model
Discovered electrons Atoms were made of
positive stuff Negative electron
floating around “Plum-Pudding”
model
![Page 6: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/6.jpg)
Ernest Rutherford’s Model Discovered dense
positive piece at the center of the atom- nucleus
Electrons would surround it
Mostly empty space “Nuclear model”
![Page 7: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/7.jpg)
Niels Bohr’s Model He had a question: Why don’t the
electrons fall into the nucleus? Move like planets around the sun. In circular orbits at different levels. Amounts of energy separate one level
from another. “Planetary model”
![Page 8: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/8.jpg)
Bohr’s planetary model Energy level of an electron analogous to the rungs of a ladder electron cannot exist between energy
levels, just like you can’t stand between rungs on ladder
Quantum of energy required to move to the next highest level
![Page 9: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/9.jpg)
The Quantum Mechanical Model
Energy is quantized. It comes in chunks. A quanta is the amount of energy needed to
move from one energy level to another. Since the energy of an atom is never “in
between” there must be a quantum leap in energy.
Erwin Schrodinger derived an equation that described the energy and position of the electrons in an atom
![Page 10: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/10.jpg)
Things that are very small behave differently from things big enough to see.
The quantum mechanical model is a mathematical solution
It is not like anything you can see.
The Quantum Mechanical Model
![Page 11: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/11.jpg)
Has energy levels for electrons.
Orbits are not circular. It can only tell us the
probability of finding an electron a certain distance from the nucleus.
The Quantum Mechanical Model
![Page 12: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/12.jpg)
The atom is found inside a blurry “electron cloud”
A area where there is a chance of finding an electron.
Draw a line at 90 % Think of fan blades
The Quantum Mechanical Model
![Page 13: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/13.jpg)
Atomic Orbitals Principal Quantum Number (n) = the
energy level of the electron. Within each energy level, the complex
math of Schroedinger’s equation describes several shapes.
These are called atomic orbitals - regions where there is a high probability of finding an electron.
![Page 14: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/14.jpg)
Summary
s
p
d
f
# of shapes
Max electrons
Starts at energy level
1 2 1
3 6 2
5 10 3
7 14 4
![Page 15: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/15.jpg)
By Energy Level First Energy Level only s orbital only 2 electrons 1s2
Second Energy Level
s and p orbitals are available
2 in s, 6 in p 2s22p6
8 total electrons
![Page 16: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/16.jpg)
By Energy Level Third energy level s, p, and d
orbitals 2 in s, 6 in p, and
10 in d 3s23p63d10
18 total electrons
Fourth energy level s,p,d, and f orbitals 2 in s, 6 in p, 10 in
d, and 14 in f 4s24p64d104f14
32 total electrons
![Page 17: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/17.jpg)
By Energy Level Any more than
the fourth and not all the orbitals will fill up.
You simply run out of electrons
The orbitals do not fill up in a neat order.
The energy levels overlap
Lowest energy fill first.
![Page 18: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/18.jpg)
Electron Arrangement in Atoms OBJECTIVES:
Apply • the aufbau principle• Pauli’s exclusion principle• Hund’s rule
For electron configurations.
![Page 19: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/19.jpg)
Section 13.2Electron Arrangement in Atoms
OBJECTIVES: Explain why the electron
configurations for some elements differ from those assigned using the aufbau principle.
![Page 20: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/20.jpg)
Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
Aufbau diagram
![Page 21: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/21.jpg)
Electron Configurations The way electrons are arranged in
atoms. Aufbau principle- electrons enter the
lowest energy first. This causes difficulties because of the
overlap of orbitals of different energies. Pauli Exclusion Principle- at most 2
electrons per orbital - different spins
![Page 22: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/22.jpg)
Electron Configuration Hund’s Rule- When electrons
occupy orbitals of equal energy they don’t pair up until they have to.
Let’s determine the electron configuration for Phosphorus
Need to account for 15 electrons
![Page 23: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/23.jpg)
The first two electrons go into the 1s orbital
Notice the opposite spins
only 13 more to go...
Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
![Page 24: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/24.jpg)
The next electrons go into the 2s orbital
only 11 more...Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
![Page 25: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/25.jpg)
• The next electrons go into the 2p orbital
• only 5 more...Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
![Page 26: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/26.jpg)
• The next electrons go into the 3s orbital
• only 3 more...Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
![Page 27: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/27.jpg)
Incr
easi
ng e
nerg
y
1s
2s
3s
4s
5s6s
7s
2p
3p
4p
5p
6p
3d
4d
5d
7p 6d
4f
5f
• The last three electrons go into the 3p orbitals.
• They each go into separate shapes
• 3 unpaired electrons
• = 1s22s22p63s23p3
![Page 28: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/28.jpg)
The easy way to remember
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2
• 2 electrons
![Page 29: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/29.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2
• 4 electrons
![Page 30: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/30.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
• 12 electrons
![Page 31: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/31.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
3p6 4s2
• 20 electrons
![Page 32: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/32.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
3p6 4s2 3d10 4p6
5s2
• 38 electrons
![Page 33: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/33.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
3p6 4s2 3d10 4p6
5s2 4d10 5p6 6s2
• 56 electrons
![Page 34: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/34.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
3p6 4s2 3d10 4p6
5s2 4d10 5p6 6s2
4f14 5d10 6p6 7s2
• 88 electrons
![Page 35: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/35.jpg)
Fill from the bottom up following the arrows
1s2s 2p3s 3p 3d4s 4p 4d 4f
5s 5p 5d 5f6s 6p 6d 6f7s 7p 7d 7f
• 1s2 2s2 2p6 3s2
3p6 4s2 3d10 4p6
5s2 4d10 5p6 6s2
4f14 5d10 6p6 7s2
5f14 6d10 7p6 • 108 electrons
![Page 36: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/36.jpg)
Exceptional Electron Configurations
![Page 37: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/37.jpg)
Orbitals fill in order Lowest energy to higher energy. Adding electrons can change the
energy of the orbital. Half filled orbitals have a lower energy. Makes them more stable. Changes the filling order
![Page 38: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/38.jpg)
Write these electron configurations
Titanium - 22 electrons 1s22s22p63s23p64s23d2
Vanadium - 23 electrons 1s22s22p63s23p64s23d3
Chromium - 24 electrons 1s22s22p63s23p64s23d4 expected But this is wrong!!
![Page 39: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/39.jpg)
Chromium is actually: 1s22s22p63s23p64s13d5
Why? This gives us two half filled orbitals. Slightly lower in energy. The same principal applies to
copper.
![Page 40: Chapter 13 Electrons in Atoms. Section 13.1 Models of the Atom OBJECTIVES: l Summarize the development of atomic theory.](https://reader036.fdocuments.in/reader036/viewer/2022062307/551c4681550346b1458b47dc/html5/thumbnails/40.jpg)
Copper’s electron configuration
Copper has 29 electrons so we expect: 1s22s22p63s23p64s23d9
But the actual configuration is: 1s22s22p63s23p64s13d10
This gives one filled orbital and one half filled orbital.
Remember these exceptions: d4, d9