1. LEWIS DOT DIAGRAMS

2. LEWIS DOT DIAGRAMS
Draw: H2O
H O H

3. LEWIS DOT DIAGRAMS
Draw: H2O
H O H
1+ 6+ 1 =8 electrons

4. LEWIS DOT DIAGRAMS
Draw: H2O
H O H
4 electrons remaining
1+6+1=8 electrons

5. LEWIS DOT DIAGRAMS
Draw: H2O
H O H
4 electrons remaining
The octets on hydrogen
are already full.

6. LEWIS DOT DIAGRAMS
Draw: H2O
H O H
0 electrons
4 electrons remaining

7. LEWIS DOT DIAGRAMS
Draw: H2O
H O H
0 electrons remaining
Oxygen has a full octet, so
there is no need to form double
or triple bonds in this case

8. LEWIS DOT DIAGRAMS
Draw: SO2
O S O

9. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
6 + 6 + 6 = 18 electrons

10. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
14 electrons remaining
6+6+6=18 electrons

11. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
2 electrons
14 electrons remaining

12. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
2 electrons
0 electrons

13. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
0 electrons
Now all atoms have a full octet

14. LEWIS DOT DIAGRAMS
Draw: SO2
O S O
The double
bond can be on
either side
O S O
These are called resonance
structures.
SO2 has 2 resonance structures

15. LEWIS DOT DIAGRAMS
Draw: PO43-
O
O P O
O

16. LEWIS DOT DIAGRAMS
Draw: PO43-
6
6
O 6
O P O 5
O
6
6+6+6+6+5=29 +3 = 32 electrons

17. LEWIS DOT DIAGRAMS
Draw: PO43-
O
O P O
O
24 electrons
6+6+6+6+5+3=32 electrons

18. LEWIS DOT DIAGRAMS
Draw: PO43-
O
O P O
O
0 electrons
24 electrons remaining

19. LEWIS DOT DIAGRAMS
Draw: PO43-
O
O P O
O
0 electrons remaining
There are no electrons left to
place

20. LEWIS DOT DIAGRAMS
Draw: PO43-
O
O P O
O
Now all atoms have a full octet

21. LEWIS DOT DIAGRAMS
Draw: PO43-
3-
O
O P O
O
Just one more thing…