1. Materials of Life Chemical Bonding Biology I Wolfe

2. Think Pair Share Name the 3 types of chemical bonds you have read or heard about. How do these chemical bonds differ from one another?

3. Three Types of Chemical Bonds Covalent Ionic Hydrogen

4. What are valence electrons? 1p

5. Let’s look at some atoms to figure out their valence electrons.

6. And this one?

7. Is there an easier way to figure out Valence Electrons…?

8. We can look at the Periodic Table Yes the colors all mean something The colors represent the # of e-’s in outer shell. 1 2 8 7 34 5 6

9. Let’s Practice… VIIIA

10. Why do Atoms bond? It is all about the Valence Electrons… Let’s review.

11. Rules for Electron Shells The first shell can only hold 2 e- All of the other ones can hold a maximum of 8 e- An atom is not “happy” or “stable” unless it’s outer shell is full. If it only has one shell, it is stable with 2 e- If it has 2 or more shells it is only stable with 8e- in it’s outer shell These outer shells are called Valence shells.

12. How many e-’s would each atom need to become “happy” or “stable”

13. Try this one on your own

14. Try These 1 2 34

15. Okay…Now about the Bonding So in order for atoms to fill that outer shell, they can either Share OR they can gain/ lose an electron. Lets talk about sharing first…

16. Covalent Bond When two or more atoms SHARE valence electrons. o (Remember Co-chairs Share Duties like electrons are shared in a Covalent bond). Hey Check out the memory cue!

18. Here comes a Tricky one…

19. How do we represent that two atoms are bonding???? This line represents two shared electrons… or a bond!

20. Now you try it CH4

21. Try these H 2 NH 3 H-H H-N-H H

22. Single, Double, Triple, Bonds

23. Try this one, it’s tricky… CO 2 First think… how many things does carbon want to bond with? Next… how many things does O want to bond with? Will they be happy if they single bond?

24. Covalent Bonds – How to Spot Them. In the periodic table non-metals always covalently bond with other non- metals. They are the elements shown in yellow on this periodic table.

25. Ions When an atom gains or loses an electron it becomes a charged ion. If the atom loses an electron it will have one more proton than electron and therefore a +1 charge. The atom which gained the electron will have one more electron than proton and therefore a –1 charge.

27. Ionic Bond

30. Ionic Bonds- How to Spot Them. Ionic bonds form between metals and non- metals. Metals are the elements in blue on this periodic table. Non-metals are the elements in yellow.

31. Isotopes When 2 atoms of the same element have different numbers of neutrons, (different atomic masses). C12 has 6 protons, 6 electrons and 6 neutrons. C14 has 6 protons, 6 electrons and 8 neutrons. C12 and C14 are isotopes of one another.

33. Non-polar Covalent Polar Covalent

34. Hydrogen bonds

35. Review What is an Ion? What is an ionic bond? What is a covalent bond? What is a hydrogen bond? What is an Isotope?

36. Interactive Periodic Table http://www.dayah.com/periodic/