The valence electrons are the electrons in the outermost principal energy level. They are
always "s'� or "sand p" electrons. �in9eJhEl tc::>JaLnumb€)r of electrons possib le ins and p
sublevels is .eight, there can be np more than eight valen9e electrons.
' · Oetermine the number of valenGe elecfrons in the otoms below.
Example: dGrbon
El�Btrdn co�fl�tfr6tioR I$ ls2
I
2s2 2p2
Carbon has 4 valence. electrons.
l. fluorine
11. lithium
2. phosphorus
12. zinc
3. calc ium
13. carbon
4. nitrogen
14. iodine
5. iron
15. oxygen
6. argon
16. barium
7. potassium
17. aluminum
8. helium
18. hydrogen
· 9. magnesium
19. xenon
10. sulfur
20. copper
Chemistry IF8766
31
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Lewis diagrams are a way to Indicate the number of valence electrons around an atom.
• .· qre qll exqrnpl,sc:>f
this type of diagrqro .. >,
Draw Lewis dot dlqgrams of the following atoms.
1. calcium
6. carbon
2. potassium
7. helium
3. argon
8. oxygen
4. aluminum
9. phosphorus
5. bromine
y
Chemistr IF8766
10. hydrogen
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