Scientific Tutor
Chem – Bohr Model and Electron Shells Part 2
Author: Andrew
What sections should I know before attempting to learn this section?
—> Bohr Model and Electron Shells Part 1
How many electrons are in the last electron shell of an element?
In the previous section we described how the Bohr Model relates to the amount of electron shells of an element. Now we are going to ask the more detailed question from above.
Examples: How many electrons are in the last electron shell of each pure element? Use the electron shells periodic table to solve.
| He | 2 |
| C | 4 |
| S | 6 |
VIDEO Electron Shell Demonstrated Example 1: How many electrons are in the last electron shell of pure Si? Use the electron shells periodic table to solve.
What period (row) is Si in?
Answer: 3
With what element does period 3 start with?
Answer: Na
How many elements do I have to count including Na until I get to Si on period 3?
Answer: 4
So how many electrons does Si have in its last electron shell?
COMPLETE ANSWER: 4 electrons in the last electron shell
PRACTICE PROBLEMS: How many electrons are in the last electron shell of each pure element? Use the electron shells periodic table to solve.
| Cl | 7 |
| Ne | 8 |
| Al | 3 |
| Be | 2 |
| B | 3 |
| O | 6 |
Posted in Chemistry
