Bohr Models and

Lewis Dot Structures

Bohring

Bohr/Lewis Dot Models

Used to predict reactivity in elements

Reactivity - how likely an element is to form a compound with another element, based on valence electrons

Drawing Bohr Models

1. Draw the nucleus.

Drawing Bohr Models

1. Draw the nucleus.

2. Write the number of Protons and Neutrons in the nucleus

P:9

N:10

Drawing Bohr Models

3. Draw the first shell

P:9

N:10

Drawing Bohr Models

3. Draw the first shell

4. Add the electrons, the first shell can only hold 2

P:9

N:10

Drawing Bohr Models

5. Draw the next shell if you

have more electrons to add

P:9

N:10

Drawing Bohr Models6. Add your electrons, the 2nd

shell can hold up to 8

Be sure to add them one at a time going clock wise.

P:9

N:10

Drawing Bohr Models7. Check yours Valence

electrons

P:9

N:10

Drawing Bohr Models7. Check yours Valence

electrons

P:9

N:10

Rules for Energy Levels

Keep adding shells until you use up all of your electrons. Here is how many each shell holds:

Shell 1: 2

Shell 2: 8

Shell 3: 18

Shell 4: 32

Practice! Woohoo!

Draw the Bohr Model for Nitrogen

More Practice! Yaaaaay!

Draw the Bohr Model for Boron

But all of this is a lie….

Rules for Energy Levels

Keep adding shells until you use up all of your electrons. Here is how many each shell holds:

Shell 1: 2

Shell 2: 8

Shell 3: 18

Shell 4: 32

Who came up with the orbitals

that we just looked at?

Schroedinger! :D

Lewis Dot Structures

These are more useful and we will use them

more often than Bohr models….

…created by Gilbert Lewis.

He also discovered the

covalent bond

Drawing Lewis Dot Structures

All you need are the number of valence electrons.

Fluorine has 7 valence electrons

Drawing Lewis Dot Structures

1. Write the letter(s) for the element to represent the nucleus.

F

Drawing Lewis Dot Structures

2. Add the valence electrons in the same way as Bohr models, go clockwise

F

Guided Practice

Number of Valence Electrons: _____6

Guided Practice

Number of Valence Electrons: _____5

Guided Practice

Number of Valence Electrons: _____1