Methods of predicting the arrangement and location of electrons in atoms Electron Arrangement.
5.2 Electron Arrangement in Atoms - Skyline...
Transcript of 5.2 Electron Arrangement in Atoms - Skyline...
![Page 1: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/1.jpg)
© Copyright Pearson Prentice Hall
Slide 1 of 20
Electron Arrangement in Atoms 5.2
![Page 2: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/2.jpg)
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
>
Slide 2 of 20
Electron Configurations
Electron Configurations
What are the three rules for writing the electron configurations of elements?
5.2
![Page 3: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/3.jpg)
Slide 3 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Electron Configurations
The ways in which electrons are arranged in various orbitals around the nuclei of atoms are called electron configurations.
Three rules—the aufbau principle, the Pauli exclusion principle, and Hund’s rule—tell you how to find the electron configurations of atoms.
5.2
![Page 4: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/4.jpg)
Slide 4 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Electron Configurations
Aufbau Principle
According to the aufbau principle, electrons occupy the orbitals of lowest energy first. In the aufbau diagram below, each box represents an atomic orbital.
5.2
![Page 5: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/5.jpg)
Slide 5 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Electron Configurations
Pauli Exclusion Principle
According to the Pauli exclusion principle, an atomic orbital may describe at most two electrons. To occupy the same orbital, two electrons must have opposite spins; that is, the electron spins must be paired.
5.2
![Page 6: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/6.jpg)
Slide 6 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Electron Configurations
Hund’s Rule
Hund’s rule states that electrons occupy orbitals of the same energy in a way that makes the number of electrons with the same spin direction as large as possible.
5.2
![Page 7: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/7.jpg)
Slide 7 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Electron Configurations
Orbital Filling Diagram
5.2
![Page 8: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/8.jpg)
© Copyright Pearson Prentice Hall
Slide 8 of 20
![Page 9: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/9.jpg)
© Copyright Pearson Prentice Hall
Slide 9 of 20
Practice Problems for Conceptual Problem 1.1
![Page 10: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/10.jpg)
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
>
Slide 10 of 20
Exceptional Electron Configurations
Exceptional Electron Configurations
Why do actual electron configurations for some elements differ from those assigned using the aufbau principle?
5.2
![Page 11: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/11.jpg)
© Copyright Pearson Prentice Hall
Slide 11 of 20
Electron Arrangement in Atoms
> Exceptional Electron Configurations
Some actual electron configurations differ from those assigned using the aufbau principle because half-filled sublevels are not as stable as filled sublevels, but they are more stable than other configurations.
5.2
![Page 12: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/12.jpg)
Slide 12 of 20
© Copyright Pearson Prentice Hall
Electron Arrangement in Atoms
> Exceptional Electron Configurations
Exceptions to the aufbau principle are due to subtle electron-electron interactions in orbitals with very similar energies.
Copper has an electron configuration that is an exception to the aufbau principle.
5.2
![Page 13: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/13.jpg)
© Copyright Pearson Prentice Hall
Slide 13 of 20
5.2 Section Quiz.
1. Identify the element that corresponds to the following electron configuration: 1s22s22p5.
a. F
b. Cl
c. Ne
d. O
![Page 14: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/14.jpg)
© Copyright Pearson Prentice Hall
Slide 14 of 20
5.2 Section Quiz.
2. Write the electron configuration for the atom N.
a. 1s22s22p5
b. 1s22s22p3
c. 1s22s1p2
d. 1s22s22p1
![Page 15: 5.2 Electron Arrangement in Atoms - Skyline Chemistryskylinechemistry.weebly.com/.../0/21101182/electron... · Electron Arrangement in Atoms > Exceptional Electron Configurations](https://reader030.fdocuments.in/reader030/viewer/2022040410/5ed2020d3dafc82aeb3aa65c/html5/thumbnails/15.jpg)
© Copyright Pearson Prentice Hall
Slide 15 of 20
`
3. The electron configurations for some elements differ from those predicted by the aufbau principle because the
a. the lowest energy level is completely filled.
b. none of the energy levels are completely filled.
c. half-filled sublevels are less stable than filled energy levels.
d. half-filled sublevels are more stable than some other arrangements.
5.2 Section Quiz.