1. Nuclear Chemistry Chapter 19

2. Define radioactivity. Complete half-life calculations. Complete and interpret nuclear reactions. Identify types of radioactive decay. Explain how fusion and fission occur. Objectives

3. Chemical Reactions vs Nuclear Reactions

4. The mass must be conserved The atomic number must be conserved. Nuclear Reactions

6. Certain numbers of neutrons and protons are extra stable − n or p = 2, 8, 20, 50, 82 and 126 − Like extra stable numbers of electrons in noble gases (e - = 2, 10, 18, 36, 54 and 86) Nuclei with even numbers of both protons and neutrons are more stable than those with odd numbers of neutrons and protons All isotopes of the elements with atomic numbers higher than 83 are radioactive All isotopes of Tc and Pm are radioactive Nuclear Stability

8. Types of Nuclear Decay

9. Energy of Radioactivity

10. Nuclear Stability and Radioactive Decay Beta decay 14 C 14 N + 0  6 7 40 K 40 Ca + 0  19 20 1 n 1 p + 0  0 1 Decrease # of neutrons by 1 Increase # of protons by 1 Positron decay 11 C 11 B + 0  6 5 +1 38 K 38 Ar + 0  19 18 +1 1 p 1 n + 0  1 0 +1 Increase # of neutrons by 1 Decrease # of protons by 1

11. Nuclear Stability and Radioactive Decay Electron capture decay Increase number of neutrons by 1 Decrease number of protons by 1 37 Ar + 0 e 37 Cl 18 17 55 Fe + 0 e 55 Mn 26 25 1 p + 0 e 1 n 1 0 Alpha decay Decrease number of neutrons by 2 Decrease number of protons by 2 212 Po 4 He + 208 Pb 84 282 Spontaneous fission 252 Cf 2 125 In + 2 1 n 98 490

13. Complete the following nuclear reaction equations.

14. Alpha decay for Thorium-232 Plutonium-244 undergoes beta decay Radon-222 decays into Astatine-210 Francium-223 emits a gamma particle

15. What Are Your Questions?

16. The amount of time it takes for half a given amount of material to radioactively decay into something else. What is Half-Life?

17. Initial Amount After 1 Half-Life After 2 Half-Lives After 3 Half-Lives

18. Based solely on the following half-lives, which radioactive atom listed is the most radioactive? A.C-14 (5730 yrs) B.Ra-226 (1620 yrs) C.U-238 (4.5 million yrs) D.Po-214 (1.6 ms) E.P-32 (14 days)

19. Radioactive Dating Radiocarbon Dating 14 N + 1 n 14 C + 1 H 716 0 14 C 14 N + 0  + 6 7 t ½ = 5730 years Uranium-238 Dating 238 U 206 Pb + 8 4  + 6 0  92822 t ½ = 4.51 x 10 9 years = t½t½ 0.693

20. A 4.5 gram sample of radon decomposes over 3 half lives. How much of the sample remains?

21. The half-life of C-14 is 5730 years. How long will it take for 50% of 25g of C-14 to decompose? How long will it take for 75% to decompose?

22. An artifact contains 12.5% of the original amount of C-14. How old is this sample? (C-14 half-life is 5730 years.)

23. The half-life of the beta particle emitter tritium, 3 H, is 12 years. How much of a 1.00 g sample of 3 H remains after 48 years?

24. What Are Your Questions?

25. Fusion and Fission https://www.youtube.com/watch?v=FU6y1XIADdg

26. Nuclear Fusion Reactor https://www.youtube.com/watch?v=MGj_aJz7cTs

27. Medical Uses for Radioactive Isotopes

28. Use nuclear reactions to create an intense explosion. The Manhattan Project Project the ran from 1942-46 to develop atomic bombs. https://www.youtube.com/watch?v=4IqKdf6In_k Nuclear Weapons

29. Three Mile Island (1979) Partial Meltdown in Pennsylvania Chernobyl (1986) Reactor 4 meltdown in Ukraine https://www.youtube.com/watch?v=vPOrywC0k9I Time 3:06 https://www.youtube.com/watch?v=vPOrywC0k9I Fukushima (2011) Three of six nuclear reactors melted down in Japan as a result of a tsunami https://www.youtube.com/watch?v=rySfb7OUFXc Nuclear Disasters

30. What Are Your Questions?