1. Interpreting Atomic Structure

2. Interpreting Atomic Diagrams
# of shells an atom has depends upon # of electrons
Each shell must have its full # of electrons before a new shell starts
If there are more electrons than a shell can hold , a new shell starts
Valence shell can hold only up to 8 electrons

3. Hydrogen # Protons= ______________ #neutrons=______________
#electrons=______________
Overall charge=___________
How many electron shells does a hydrogen atom have? e P

4. Helium e # Protons= ______________ #neutrons=______________
#electrons=______________
Overall charge=___________
How many electron shells does a helium atom have?
Is the shell full? P N P N e

5. Beryllium # Protons= ______________ #neutrons=______________
#electrons=______________
Overall charge=___________
How many electron shells does beryllium have?
Is the inner shell full?
Is the outer shell full? e P N P N P N e e N N P e

6. Oxygen # Protons= ______________ #neutrons=______________
#electrons=______________
Overall charge=___________
How many electron shells does oxygen have?
Is the inner shell full?
Is the outer shell full? e e e P N P P N P N N e e N N N P N N P P P e e e

7. www.middleschoolscience.com 2008
How to Draw Bohr Diagrams
2008

8. Bohr Diagrams Find your element on the periodic table.
Determine the number of electrons – it is the same as the atomic number.
This is how many electrons you will draw.

9. Bohr Diagrams Find out which period (row) your element is in.
Elements in the 1st period have one energy level.
Elements in the 2nd period have two energy levels, and so on.

10. Bohr Diagrams
The families/groups tell us how many valence electrons an element has
How many valence electrons does the following elements have? H He B O Ne

11. C Bohr Diagrams Draw a nucleus with the element symbol inside.
Carbon is in the 2nd period, so it has two energy levels, or shells.
Draw the shells around the nucleus. C

12. C Bohr Diagrams Add the electrons. Carbon has 6 electrons.
The first shell can only hold 2 electrons. C

13. Bohr Diagrams
Since you have 2 electrons already drawn, you need to add 4 more.
These go in the 2nd shell.
Add one at a time -starting on the right side and going counter clock-wise. C

14. C Bohr Diagrams Check your work.
You should have 6 total electrons for Carbon.
Only two electrons can fit in the 1st shell.
The 2nd shell can hold up to 8 electrons.
The 3rd shell can hold 18, but the elements in the first few periods only use 8 electrons. C

15. Bohr Diagrams
Try the following elements on your own: H He O Al Ne K C

16. H Bohr Diagrams Try the following elements on your own: H – 1 electronAl Ne K H

17. Bohr Diagrams He Try the following elements on your own: H
He - 2 electrons O Al Ne K He

18. Bohr Diagrams O Try the following elements on your own: H He
O - 8 electrons Al Ne K O

19. Bohr Diagrams Al Try the following elements on your own: H He O
Al - 13 electrons Ne K Al

20. Bohr Diagrams Ne Try the following elements on your own: H He O Al
Ne - 10 electrons K Ne

21. Bohr Diagrams K Try the following elements on your own: H He O Al Ne
K - 19 electrons K