1. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Chemistry FIFTH EDITION Chapter 21 The Nucleus: A Chemist’s View

2. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 2 Types of Radioactive Decay alpha production (  ): helium nucleus, beta production (  ):

3. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 3 Figure 21.1 The Zone of Stability

4. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 4 Types of Radioactive Decay gamma ray production (  ): positron production: electron capture: (inner-orbital electron is captured by the nucleus)

5. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 5 Decay Series A radioactive nucleus reaches a stable state by a series of steps.

6. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 6 Figure 21.2 A Decay Series

7. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 7 Rate of Decay rate = kN The rate of decay is proportional to the number of nuclides. This represents a first- order process.

8. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 8 Figure 21.3 The Decay of a 10.0g Sample of Strontium-90 Over Time

9. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 9 Half-Life...the time required for the number of nuclides to reach half the original value (N 0 /2).

10. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 10 Figure 21.4 Change Over Time

11. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 11 Nuclear Transformation The change of one element into another.

12. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 12 Figure 21.5 A Schematic Diagram of a Cyclotron

13. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 13 Figure 21.6 A Schematic Diagram of a Linear Accelerator

14. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 14 Energy and Mass  m = mass defect  E = change in energy If  E =  (exothermic), mass is lost from the system. When a system gains or loses energy it also gains or loses a quantity of mass.  E =  mc 2

15. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 15 Binding Energy...is the energy required to decompose the nucleus into its components. has a binding energy per nucleon of 8.79 MeV Iron-56 is the most stable nucleus.

16. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 16 Figure 21.9 The Binding Energy Per Nucleon as a Function of Mass Number

17. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 17 Nuclear Fission and Fusion Fusion: Combining two light nuclei to form a heavier, more stable nucleus. Fission: Splitting a heavy nucleus into two nuclei with smaller mass numbers.

18. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 18 Figure 21.11 Fission

19. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 19 Fission Processes A self-sustaining fission process is called a chain reaction.

20. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 20 Figure 21.13 Fission Produces Two Neutrons

21. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 21 Figure 21.12 Fission Produces a Chain Reaction

22. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 22 Key Parts of a Fission Reactor 4 Coolant 4 Containment Shell Reactor Core: 3% + moderator and control rods.

23. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 23 Figure 21.14 A Schematic Diagram of a Nuclear Power Plant

24. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 24 Figure 21.15 A Schematic Diagram of a Reactor Core

25. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 25 Breeder Reactors Fissionable fuel is produced while the reactor runs ( is split, giving neutrons for the creation of ):

26. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 26 Figure 21.10 Both Fission and Fusion Produce More Stable Nuclides

27. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 27 Figure 21.16 A Plot of Energy Versus Separation Distance

28. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 28 Biological Effects of Radiation... depend on: 1.Energy of the radiation 2.Penetration ability of the radiation 3.Ionizing ability of the radiation 4.Chemical properties of the radiation source

29. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 29 Figure 21.7 A Schematic Representation of a Geiger-Müller Counter