1. Bohr Model and Bonding

2. Bohr Model Review Bohr Models show us a visual representation of an atom There are two things that You need to have: The period that the element is in The number of electrons Practice the following elements

3. Bohr Practice 1 per 2 per 3 per 4 per 2 8 18 32 Argon Oxygen Neon Silicon Phosphorus

4. MAG-NE-SIUM

5. Atomic Structure Protons = + charge (positive) Neutrons = neutral Protons and Neutrons are located in the nucleus Electrons = - charge (negative) Electrons are located in electron shells or energy levels or valences. Each shell/level/valence holds a specific number of electrons

6. Which element is this? Helium

7. Argon Beryllium Barium Boron

8. Why do we have bonding? Elements struggle to become “Happy”. Being happy means having a full orbital= “8 electrons”, some elements have too many electrons and want to give up some electrons, some have too little electrons and want to gain some electrons. In order to be stable, elements will either “transfer” or “share” electrons with each other

9. Lets look at some examples Level/shell/valence = period Outer electrons = group Some elements have only a couple of electrons in their outer shells, for them it’s easier to give up their few electrons

10. More examples Others are interested in gaining some electrons Remember, in order to be HAPPY they want to have 8 electrons in their outer shell.

11. AR-GON

12. PHOS-PHO-RUS

13. What do you do if you are a sodium (Na) atom? You have eleven electrons, one too many to have your shell filled. You need to find another element who will take that electron away from you. Chlorine (Cl) will take that electron away and leave you with 10 electrons inside of two filled shells. You are a happy atom. Now you are also an ion and missing one electron. You are a sodium ion (Na+). You have one less electron than your atomic number. The story of Sodium

14. The story of Sodium continued So now you've become a sodium ion (Na+). Now you have ten electrons. That's the same number as neon (Ne). But you aren't neon (Ne). Since you're missing an electron you aren't really a complete sodium (Na) atom either. You are now something completely new. An ion. Other electrically charged atoms (ions) are now looking at you and seeing a good partner to bond with. That's where chlorine comes in.

15. Two types of bonds Ionic Ionic bonds are just groups of charged ions held together by electric forces between metals and nonmetals Covalent Covalent bonds are where the electrons are shared between two atoms between non metals Ionic Bonds

16. Which type of bond is Sodium? Sodium would be an ionic bond Evidence: Ions are formed Electrons are given to another atom Sodium looks for other ions to bond with Vision Learning website

18. NI-TRO-GEN

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