2. Educational Communications and Technology EDD 5161A Group 7 Chemistry Topic: Chemical Bonding

3. Group Members F Chan Lam Fai Chemistry F Wong Wai YinChemistry F Cheung Lai NeiChemistry

4. Chemical Bonding

5. Introduction F What will happen when two magnet put together? Why? F MAGNETIC FORCE caused 2 magnets stick together.

6. Bonding F ELECTROSTATIC FORCE caused 2 atoms join together. F Force between 2 atoms caused BONDING.

7. Types of Bonding

9. Ionic Bond F What is the chemical formula of salt? F NaCl F Is NaCl neutral or a charge carrier? F Neutral

10. Ionic Bond (Cont’d) F After dissolving in water, what would the elements become? F Ions F Are they neutral or charged? F Charged

11. Ionic Bond (Cont’d) F Which is positive / negative charge? F Sodium ion, Na +, — positive F Chloride ion, Cl –, — negative

12. Definition of Ionic Bond F IONIC BOND is the strong non-directional electrostatic force of attraction between oppositely charge ions. F A pure ionic bond is formed by the COMPLETE transfer of one or more electrons from one atom to another.

13. Electron Transfer of NaCl F Na is metal or non-metal? How about Cl? F Na is metal, Cl is non-metal. F Generally, electron transfers from Na (metal) to Cl (non-metal). F Why?

14. Electronic Configuration of Na F What is the electronic configuration of Na? F (2,8,1) F Na tend to loss or gain electron to make it stable? F It tends to loss ONE electron to make it stable.

15. Sodium Ion Losing one electron

16. Electronic Configuration of Cl F What is the electronic configuration of Cl? F (2,8,7) F Cl tend to loss or gain electron to make it stable? F It tends to gain ONE electron to make it stable.

17. Chloride Ion Gaining one electron

18. Electronic Diagram of NaCl F The electron transfer from sodium atom to chlorine atom. F It is also called an electron ‘dot/cross’ diagram (or simply electron diagram) F Simplified notation

19. Another Example Let’s consider another example, magnesium fluoride. F What is the chemical formula of magnesium fluoride? F MgF 2

20. Another Example (Cont’d) F Which one lose electron(s)? How many? F Mg loses 2 electrons. F Which one gain electron(s)? How many? F F gain 1 electron.

21. Another Example (Cont’d) F How many atoms of Mg and F involved in this electron transfer process? F 1 Mg atom, 2 F atoms F So, totally 3 atoms are involved in this process.

22. Magnesium Fluoride MgF 2 What your prediction about the electronic transfer of MgF 2

23. Homework F Draw the electronic diagram of the following compounds. –Potassium Chloride –Magnesium Chloride –Aluminum Chloride

24. ~ The End ~