1. Chapter 15 Ionic Bonding and Ionic Compounds
Electron Configuration in Ionic Bonding
Ionic Bonds
Bonding in Metals

2. Electron Configuration in Ionic Bonding
Valence Electrons
Electron Configuration for Cations
Electron Configuration forAnions

3. Valence Electrons The electrons in the highest occupied energy level
The number of valence electrons determines the chemical properties
All elements in a group have the same number of valence electrons

4. Valence Electrons
The number of valence electrons is related to the group number
Group 1  1 valence electron
Group 2  2 valence electrons, …
Exception: Helium

5. Valence Electrons
Only valence electrons are shown in an electron dot diagram.

6. Electron Configuration for Cations
Octet Rule: In forming compounds, atoms tend to achieve eight electrons or the electron configuration of a noble gas.
Metallic elements lose their valence electrons to obtain the octet
Na  Na+ + e
2-8-1  2-8

7. Electron Configuration for Cations
Cation – ion with a positive charge (lose electrons)
Some transition metals due not form octets when they lose electrons and they are exceptions
Ag (needs to lose 11 electrons to be Krypton or gain 7 electrons to be Xenon)
Loses only 1 electon

8. Electron Configuration for Anions
Anion – ion with a negative charge (gains electrons)
Cl  Cl-
Halide ions – halogens that have gained an electron

9. Chapter 15.2 Formation of Ionic Compounds
Properties of Ionic Compounds

10. Formation of Ionic Compounds
Ionic Bonds – forces of attraction between cations and anions (electrostatic forces)
NaCl
Na lose 1 electron, becoming positively charged
Cl gains 1 electron becoming negatively charged
Opposite charges attract each other

11. Properties of Ionic Compounds
Room Temperature, most ionic compounds are crystalline structures

12. NaCl

13. BaSO4 (Barite)

14. BeAl2(SiO3)6 (Beryl)

15. Franklinite

16. Hematite

17. Properties of Ionic Compounds
High melting points due to very stable structures due to large attractive forces
When melted, can conduct electricity
When aq, can conduct electricity

18. Chapter 15.3 Bonding in Metals
Metallic Bonds and Metallic Properties
Crystalline Structures of Metals
Alloys

19. Metallic Bonds Metals are made up of closely packed cations
Surrounded by mobile valence electrons which drift freely from one part of the metal to another
Metallic Bonds – attraction of free floating valence electrons for positively charged metal ions

20. Metallic Properties Good conductors of electricity
Ductile – Can be drawn into wires
Malleable – can be hammered into shapes

21. Crystalline Structures of Metals
Metals are also crystals just like ionic compounds are crystals

22. Body Centered Cubic - Chromium

23. Face Centered Cubic - Gold

24. Hexagonal Close Packed – Zinc

25. Alloys
Mixture of two or more elements in which at least one is a metal

26. Brass
Copper and Zinc

27. Sterling Silver
Silver (92.5%) and Copper (7.5%)

28. Coinage Silver
Silver (90%) and Copper (10%)

29. Cast Iron
Iron (96%) and Carbon (4%)

30. Stainless Steel
Iron (80.6%), Chromium(18%), Carbon (.4%) and Nickel (1.0%)

31. Spring Steel
Iron (98.6%), Chromium(1%), Carbon (.4%)

32. Surgical Steel
Iron (67%), Chromium(18%), Nickel (12.0%) and Molybdenum (3.0%)

33. 14 K Gold (Yellow)
Gold
Copper
Silver

34. White Gold
Gold
Nickel
Zinc
Silver
Palladium

35. Why did my GOLD ring turn my skin Green?
A reaction between copper and your skin causes it to turn green or black.
The lower the “K” number, the less gold and more copper.
Gold Plated – can wear off and the filler metal can react with you skin
Nickel allergies – causes staining, itchiness and red