Quantum Transport :Atom to Transistor,What Makes Electrons Flow
Electrons in Atoms Ch. 13. Models of the Atom 13-1.
-
Upload
angel-gallagher -
Category
Documents
-
view
218 -
download
0
Transcript of Electrons in Atoms Ch. 13. Models of the Atom 13-1.
![Page 1: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/1.jpg)
Electrons in Atoms
Ch. 13
![Page 2: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/2.jpg)
Models of the Atom
13-1
![Page 3: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/3.jpg)
The evolution of Atomic Models
• Dalton (1766-1844): atom indivisible• J.J. Thomson (1856-1940):
– “Plum-pudding” model – negative electrons stuck in positively charged material
• Rutherford (1871-1937):– Electrons surround dense nucleus, rest of
atom is empty space
• Bohr (1885-1962):– “Planetary model,” electrons fixed in energy
levels around nucleus
![Page 4: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/4.jpg)
![Page 5: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/5.jpg)
The Quantum Mechanical Model
• Quantum Mechanical Model:
– Estimates the probability of finding an electron in a certain place using the Schrodinger equation.
– “Fuzzy cloud” model; where the cloud is more dense the probability of finding the electron is high, where the cloud is less dense the probability is low.
![Page 6: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/6.jpg)
Energy Levels• Electrons move around the nucleus
in energy levels.
• Quantum of energy = amount of E required to move to a higher level.
• When they move towards the nucleus (down a level) they release energy
• When they move away from the nucleus (up a level) they require energy.
• The farther from the nucleus the energy level is, the more energy is required to move up a level (away from nucleus).
![Page 7: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/7.jpg)
Energy Levels
• Quantum number (n) refers to an energy level– n = 1, 2, 3, 4, …7, values increase going away
from nucleus.– Each energy level fits a certain amount of
electrons:• Level 1 = 2 electrons• Level 2 = 8 electrons• Level 3 = 18 electrons• Level 4 = 32 electrons
![Page 8: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/8.jpg)
Sublevels + Orbitals• Within each energy level there are sublevels; the
number of sublevels is equal to the quantum number.– Ex: Energy level 4 has 4 sublevels within it.
• A sublevel is made up of atomic orbitals: s, p, d, f– Orbital s fits 2 electrons total– Orbital p fits 6 electrons total– Orbital d fits 10 electrons total– Orbital f fits 14 electrons total– s fills up first, then p, then d, then f
![Page 9: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/9.jpg)
Energy Level (n)
Sublevel/Orbital
Electrons in each
Sublevel/Orbital
Total # of electrons in
Level
1 1s 2 2
2 2s
2p
2
6 8
3 3s
3p
3d
2
6
10 18
4 4s
4p
4d
4f
2
6
10
14 32
![Page 10: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/10.jpg)
Atomic Orbitals
Orbital Shape # of Electrons
s Spherical 2
p Dumbbell 6
d Clover-leaf 10
f Complex 14
![Page 11: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/11.jpg)
DRAW!
s - orbital
p - orbital
d - orbital
f - orbital
![Page 12: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/12.jpg)
Electron Arrangement in Atoms
13-2
![Page 13: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/13.jpg)
d-1
f-2
5d1
6d1
Label + Color on white, blank, large periodic table!
![Page 14: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/14.jpg)
Electron Arrangement in Atoms
• Period 1 - 1s2
• Period 2 - 2s22p6
• Period 3 - 3s23p6
• Period 4 - 4s23d104p6
• Period 5 - 5s24d105p6
• Period 6 - 6s24f145d106p6
• Period 7 - 7s25f146d107p6
• 1s22s22p63s23p64s23d104p65s24d105p6
6s24f145d106p67s25f146d107p6
![Page 15: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/15.jpg)
Electron Configuration Notation• Notation used to represent electron
configurations:
– H: 1s1
– He: 1s2
– Li: 1s2 2s1
– Be: 1s2 2s2
– B: 1s2 2s22p1
Energy level Sub level/orbital
# of electrons in sublevel/orbital
![Page 16: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/16.jpg)
d-1
f-2
5d1
6d1
Duplicate
![Page 17: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/17.jpg)
Recommend writing configuration in each square
![Page 18: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/18.jpg)
You Try!
• C:– (6): 1s22s22p2
• F:– (9): 1s22s22p5
• Ne:– (10): 1s22s22p6
• Na:– (11)1s22s22p63s1
• P:– (15)1s22s22p63s23p3
• Ca:– (20)1s22s22p63s23p64s2
• Ir:– (77)1s22s22p63s23p64s2
3d104p65s24d105p66s2
4f145d7
• Cm:– (96)1s22s22p63s23p64s2
3d104p65s24d105p66s2
4f145d106p67s25f7
Write the electron configurations for the following:
![Page 19: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/19.jpg)
• Abbreviated form: shows preceding noble gas and the configuration of only the last energy level!– Mg: 1s2 2s22p63s2
• or [Ne] 3s2
– B: 1s2 2s2 2p1 • or [He] 2s2 2p1
– Si: 1s2 2s2 2p6 3s2 3p2 • or [Ne] 3s2 3p2
– Al: 1s2 2s2 2p6 3s2 3p1 • [Ne] 3s2 3p1
– Xe: 1s2 2s2 2p6 3s23p64s23d104p65s24d105p6
• [Kr] 5s24d105p6
![Page 20: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/20.jpg)
• What happens in the fourth period?
– After 4s2, comes 3d10, then 4p6
– Scandium (#21): 1s2 2s2 2p6 3s2 3p6 4s2 3d1
• or [Ar] 4s2 3d1
– Copper is [Ar] 4s2 3d9
– Bromine is [Ar] 4s2 3d10 4p5
• What happens in the sixth period?
– After 6s2, comes 4f14, then 5d10, then 6p6
– Tungsten (W) is [Xe] 6s24f145d4
![Page 21: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/21.jpg)
Orbital Notation Rules1) Aufbau principle: electrons enter orbitals
of lowest energy first.
2) Pauli exclusion principle: an atomic orbital may describe at most 2 electrons.
3) Hund’s rule: one electron enters each orbital until ALL orbitals contain 1 electron with parallel spins.
![Page 22: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/22.jpg)
![Page 23: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/23.jpg)
Light and Atomic Spectra
13-3
(only pg. 372-375)
![Page 24: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/24.jpg)
Electromagnetic Spectrum
• Energy in the form of electromagnetic radiation (radiant energy) travels in waves
• Waves transfer the energy from one place to another
• Ex: radio waves, TV, microwave, visible light, x-rays, gamma rays, infrared, UV
• All forms of radiant energy are part of the electromagnetic spectrum
![Page 25: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/25.jpg)
DRAW!!!
Low energy High Energy
![Page 26: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/26.jpg)
Wavelength + Frequency• Two main properties of electromagnetic
waves:
1) Frequency
2) Wavelength
• Wavelength is the distance between two corresponding peaks or troughs.
![Page 27: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/27.jpg)
• Frequency is the number of wave cycles per second.
• Wavelength is inversely proportional to frequency
• wavelength frequency
DRAW!!!
Wave lengthFrequency
Wave lengthFrequency
![Page 28: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/28.jpg)
• Higher frequency waves (short wavelength) have high energy– Ex: gamma rays, x-rays, ultraviolet rays– Ex: Violet light in visible spectrum
• Low frequency waves (long wavelength) have low energy– Ex: radio waves, microwaves, infrared (heat)
waves– Ex: Red light in visible spectrum
![Page 29: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/29.jpg)
Light and Atomic Spectra
• Electrons absorb energy and move to higher energy states/levels
• Electrons give off that energy in the form of light when they fall back down to lower energy states, or ground state.
• ALL electromagnetic waves travel at the speed of light in a vacuum – 300 million meters per second or (3.0 x 108 m/s)
![Page 30: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/30.jpg)
•When atoms are energized by an electric current they emit light.
•When this light is passed through a prism they produce an emission spectrum.
•Each element has its own unique atomic emission spectrum fingerprint
![Page 31: Electrons in Atoms Ch. 13. Models of the Atom 13-1.](https://reader035.fdocuments.us/reader035/viewer/2022062314/56649efe5503460f94c13b5c/html5/thumbnails/31.jpg)