1. Chapter Nineteen: THE REPRESENTATIVE ELEMENTS: GROUPS 1A THROUGH 4A

2. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 2 Reviewing the Periodic Table Regions Representative elements: –Groups 1A - 8A (filling s and p orbitals) Transition elements: –Center of the table (filling d orbitals) 19.1

3. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 3 Reviewing the Periodic Table Regions Lanthanides and Actinides: –Listed separately, on the bottom of the table (filling 4f and 5f orbitals) Metalloids: –Separate metals from nonmetals 19.1

4. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 4 The Atomic Radii of Some Representative Elements in Picometers

5. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 5 Alkali Metals (Group 1A): Sources and Methods of Preparation 19.2

6. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 6 Group 1A Oxides In the presence of excess oxygen: 4Li + O 2  2Li 2 O 2Na + O 2  Na 2 O 2 K + O 2  KO 2 Rb + O 2  RbO 2 Cs + O 2  CsO 2 19.2

7. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 7 Exercise Predict the products formed by the following reactants: –Na 2 O 2 (s) + H 2 O(l) –LiH(s) + H 2 O(l) 19.2

8. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 8 Hydrides Binary compounds containing hydrogen: – Ionic hydrides: hydrogen + the most active metals (eg; LiH, CaH 2 ) –Covalent hydrides: hydrogen + other nonmetals (eg; H 2 O, CH 4, NH 3 ) –Metallic (interstitial) hydrides: transition metal crystals treated with H 2 gas 19.3

9. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 9 Alkaline Earth Metals (Group 2A) Very reactive Great practical importance: –Human life (Ca and Mg) 19.4

10. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 10 Ion Exchange Ca 2+ and Mg 2+ are often removed during ion exchange, releasing Na + into solution. Ion exchange resin – large molecules that have many ionic sites. 19.4

11. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 11 A Schematic Representation of a Typical Cation-Exchange Resin 19.4

12. Copyright © Houghton Mifflin Company. All rights reserved.Chapter 19 | Slide 12 Inert Pair Effect The tendency for the heavier elements of Groups 3A and 4A to exhibit lower oxidation states as well as their expected oxidation states. Group 3A +1 and +3 oxidation states Group 4A +2 and +4 oxidation states 19.5/19.6