1. 2 - 1 CH 104 Chapter 13: Nuclear Chemistry Radioactivity Nuclear Equations Radiation Detection Half-Life Medical Applications Radiometric Dating Fission & Fusion

2. 2 - 2 CH 104

3. 2 - 3 CH 104 Isotopes of Hydrogen Isotopes = Isotopes = Atoms of the same element but having different masses. 1111 2121 3131 H H H +- +-+- Protium99.99% Deuterium0.01% Tritium Trace % Average Atomic weight Average Atomic weight of Hydrogen 1.00794 amu = 1.00794 amu

4. 2 - 4 CH 104 Isotopes of Carbon Average Atomic weight12.011 amu Average Atomic weight of C= 12.011 amu 98.89% C 612C 613 C 6141.11% Trace % + + + + ++ - --- - - - + + + + ++-- - - - + + + + ++---- - -

5. 2 - 5 CH 104 Radioactive Isotopes C 614 + + + + ++---- - - + 3131 H - Nucleus is unstable So falls apart (decays) Giving radioactive particles Hydrogen-3 Carbon-14

6. 2 - 6 CH 104 Radioactive Isotopes in Medicine Tc 4399m 123 53 53 I 131 I 6027 Co Diagnose thyroid function Treat hyperthyroid (destroys cells) Destroy tumors (  radiation) Diagnose bone, tissue (most common)

7. 2 - 7 CH 104 Alpha Decay Pb 82 206 +++ + ++ 21084 Po 42 He ++  Particle 21084 Po Pb 82 206 + 42 He Transmutation: Transmutation: one element changes to another

8. 2 - 8 CH 104 Beta Decay N 7 14 146 C 0 e -  Particle +++ + ++ +++ + ++ + + -+ -+ -+ - 10 n 11 H + 0 e neutronprotonelectron

9. 2 - 9 CH 104 Beta Decay N 7 14 146 C 0 e -  Particle +++ + ++ +++ + ++ + + -+ -+ -+ - + 0 e 146 C N 7 14

10. 2 - 10 CH 104 Gamma Decay 99m43 Tc  decay +++ + ++ +++ + ++ 9943 Tc + 99m43 Tc Tc 43 99 

11. 2 - 11 CH 104 Ionizing Radiation - Radiation knocks off an electron An ion A radical Ions & radicals cause damaging chain reactions

12. 2 - 12 CH 104 Geiger Counter - Radiation knocks off an electron An ion Ions detected by Counter Gas in instrument tube

13. 2 - 13 CH 104 Radiation: Penetration through Air ++ -  2 - 4 cm 200 - 300 cm 500 m

14. 2 - 14 CH 104 Radiation: Shielding ++ -  Paper Cloth Heavy Cloth Pb, thick concrete

15. 2 - 15 CH 104 ++ -  Tissue Penetration Depth 0.05 mm 4-5 mm 4-5 mm >50 cm

16. 2 - 16 CH 104 Nuclear Equations 22688 Ra Rn 86 222 + 42 He  Radium    Radon gas in Buildings Po 84 218 + 42 He

17. 2 - 17 CH 104 13153 I Xe 54 131 + 0 e  Thyroid check & treatment  Cancer Treatment Nuclear Equations 6027 Co Ni 28 60 + 0 e

18. 2 - 18 CH 104 Radiation Detection 1 Ci = 3.7 x 10 10 disintegrations sec 1 Bq = 1 disintegration sec # of disintegrations by of 1g Ra ActivityActivity Becquerel (Bq) Curie (Ci) Curie (Ci):

19. 2 - 19 CH 104 Radiation Detection Absorbed Dose

20. 2 - 20 CH 104 ++  -   Tissue Penetration Depth 0.05 mm 0.06-5 mm >50 cm Radiation Absorbed Dose (Rad) (D) Radiation Absorbed Dose (Rad) (D): 1 rad = 0.01 J kg tissue kg tissue 1 rad = 0.01 J kg tissue kg tissue 1 rad = 0.0024 cal kg tissue kg tissue Radiation Detection: Biological Effect 100 rad = 1 Gray

21. 2 - 21 CH 104 Radiation Detection Biological Damage

22. 2 - 22 CH 104 Roentgen Equivalent for Man (rem)    1 remW R 1 rem = 1 rad x W R W R 2011 WRWRWRWR2011 Damage (rem) = absorbed dose (rad) X factor Quality Factor (Q) = Radiation Weighting factor W R Radiation Weighting factor W R 100 rem 100 rem = 1 sievert (Sv)

23. 2 - 23 CH 104 Learning Check

24. 2 - 24 CH 104 Learning Check: Solution

25. 2 - 25 CH 104 Annual Radiation Exposure in USA Ground = 15-30 mrem Air, H 2 O, Food = 30 mrem Cosmic = 26-40 mrem Wood,concrete,bricks = 50 mrem X-rays: Chest = 50 mrem Dental = 20 Smoking Smoking = 35 mrem TV/computers = 12 mrem Radon = 200 mrem Total = 170 - 360 mrem / yr

26. 2 - 26 CH 104 Annual Radiation Exposure in USA

27. 2 - 27 CH 104 Biological Effects of Radiation Dose in rem (at one time) 0-25genetic damage possible but usually undetected 25-100 decrease # of white blood cells (temporary) 100-200 mild radiation sickness (vomit, diarrhea, strong decrease # white blood cells) >300 (diarrhea, hair loss, infection) 500LD 50 for humans Dose in rem (at one time) 0-25genetic damage possible but usually undetected 25-100 decrease # of white blood cells (temporary) 100-200 mild radiation sickness (vomit, diarrhea, strong decrease # white blood cells) >300 (diarrhea, hair loss, infection) 500LD 50 for humans

28. 2 - 28 CH 104 300 LD 50 for dogs 800 LD 50 for rats 50,000 LD 50 for Bacterium 100,000 LD 50 for Insects Biological Effects of Radiation Dose in rem 500LD 50 for humans

29. 2 - 29 CH 104 4,500 Lymphoma 5,000 – 6,000 Skin cancer 6,000 Lung cancer 6,000 – 7000 Brain Tumor Therapeutic Doses of Radiation Dose in rem

30. 2 - 30 CH 104 FDA approved killing of bacteria with: 0.3 – 1 kGy ionizing radiation from Co-60 or Cs-137 (gamma producers)

31. 2 - 31 CH 104 Half-Life t 1/2 = Time for 1/2 sample to decay 13153 I 20 g t 1/2 = 8 days 10 g 8 days 5 g

32. 2 - 32 CH 104 Half-Life I-1318 days Co-605.3 yrs Tc-99m6 hrs Ra-2261620 yrs I-1318 days Co-605.3 yrs Tc-99m6 hrs Ra-2261620 yrs

33. 2 - 33 CH 104 Half-Life t 1/2 = Time for 1/2 sample to decay 13153 I 20 g t 1/2 = 8 days 10 g 8 days 5 g Youtube: Bill Nye Explains Half Life (1:04) https://www.youtube.com/watch?v=js7weHZIQ5o

34. 2 - 34 CH 104 13153 I 20. g t 1/2 = 8 days 10. g 8 days 5.0 g How much I-131 will be left after 72 days? Half-Life 72 days 1 1 half-life = 8 days 9 9 half-lifes 20  10  5  2.5  1.25 .625 .3125 .156g

35. 2 - 35 CH 104 Learning Check: Chromium-55 undergoes beta decay wth a half life of 3.5 minutes. What is the primary identity of the sample after decay? 5524 Cr +

36. 2 - 36 CH 104 Learning Check: Solution Chromium-55 undergoes beta decay wth a half life of 3.5 minutes. What is the primary identity of the sample after decay? 5524 Cr Mn 25 55 + 0 e

37. 2 - 37 CH 104 Learning Check: Chromium-55 undergoes beta decay wth a half life of 3.5 minutes. What is the primary identity of the sample after decay? If you start with 120 g; How much Cr-55 will be left after 14 minutes? 5524 Cr Mn 25 55 + 0 e

38. 2 - 38 CH 104 Learning Check: Solution Chromium-55 undergoes beta decay wth a half life of 3.5 minutes. 5524 Cr 120 g t 1/2 = 3.5 min 60 g 3.5 min What is the primary identity of the sample after decay? If you start with 120 g; How much Cr-55 will be left after 14 minutes? 5524 Cr Mn 25 55 + 0 e (7 min Total) 3.5 min (10.5 min Tot) 3.5 min (14 min Total) 30 g 15 g7.5 g

39. 2 - 39 CH 104 23892 U Th 90 234 + 42 He 23490 Th Pa 91 234 + 0 e Natural Decay Series of Uranium-238 What is the product of alpha decay of U-238? What is the product of beta decay of U-238?

40. 2 - 40 CH 104 Natural Decay Series of Uranium-23823892 U Th 90 234 + 42 He 23490 Th Pa 91 234 + 0 e

41. 2 - 41 CH 104 Natural Decay Series of Uranium-238

42. 2 - 42 CH 104 Learning Check

43. 2 - 43 CH 104 Learning Check: Solution

44. 2 - 44 CH 104 Radiometric Dating C-14 dating of artifacts (bones, wood,….); t ½ = 5760 years + 0 e 146 C N 7 14 Issues: Production of C-14 by sun varies in atmosphere. 14 CO 2(g) amounts vary in atmosphere U-238   Pb-206U-235   Pb-207 Issues: Assumes all Pb was once U K  Ar(t ½ K-40 = 1.248 x 10 9 years) + 4020 Ca 4019 K Ar 18 40 2 Issues: Ar (g) solubility Starting amount of K-40

45. 2 - 45 CH 104 Artificial Transmutation 1 st by Rutherford (1919) New elements all artificially made in particle accelerators. YouTube: How does an atom smashing particle accelerator work? (3:26) https://www.youtube.com/watch?v=G6mmIzRz_f8 Lego particle accelerator: https://www.youtube.com/watch?v=SdmDb8ozcXchttps://www.youtube.com/watch?v=SdmDb8ozcXc

46. 2 - 46 CH 104 Fission 235 92 U 1010 n 236 92 U + 91 36 Kr 142 56 Ba unstable Splitting atoms for Energy Uses: Atomic BombAtomic Bomb Nuclear PowerNuclear PowerUses: Atomic BombAtomic Bomb Nuclear PowerNuclear Power

47. 2 - 47 CH 104 235 92 U Fission

48. 2 - 48 CH 104 235 92 U Fission

49. 2 - 49 CH 104 235 92 U Fission

50. 2 - 50 CH 104 235 92 U Fission

51. 2 - 51 CH 104 236 92 U Fission

52. 2 - 52 CH 104 91 36 Kr 142 56 Ba Fission

53. 2 - 53 CH 104 New elements all artificially made in particle accelerators. YouTube: How does an atom smashing particle accelerator work? (3:26) https://www.youtube.com/watch?v=G6mmIzRz_f8 Lego particle accelerator: https://www.youtube.com/watch?v=SdmDb8ozcXchttps://www.youtube.com/watch?v=SdmDb8ozcXcFission

54. 2 - 54 CH 104 Fission critical mass Need critical mass of U-235 to sustain chain rxn to produce enough E for an explosion

55. 2 - 55 CH 104 U-235Fission Nuclear Power plants: Controlled fission avoids critical mass Nuclear Power plants: Controlled fission avoids critical mass

56. 2 - 56 CH 104 Uses: SunSun Hydrogen BombHydrogen BombUses: SunSun Hydrogen BombHydrogen Bomb Deuterium Tritium 4242 He Fusion 2121 H 3131 H + + ++ ++ 1010 n Combining atoms for Energy 100,000,000 O C > E than from fission But impractical since heat too high > E than from fission But impractical since heat too high

57. 2 - 57 CH 104 Fusion Making radioactive particles Add 2 stable nuclei  unstable nucleus

58. 2 - 58 CH 104 Learning Check

59. 2 - 59 CH 104 Learning Check: Solution

60. 2 - 60 CH 104 Videos Video: Frontline NOVA Fukushima: Nuclear Aftershocks (53.41 min) http://video.pbs.org/video/2187854464/

61. 2 - 61 CH 104 B 5 11 116 C0+1e + 10 n 11 H + 0+1 e protonneutronpositron Positron Emission Tomography (PET)   Positron +++ ++ +0 +++ + + 0

62. 2 - 62 CH 104  rays  image Shows blood flow  rays  image Shows blood flow B 5 11 116 C0+1e + Positron Emission Tomography (PET)   Positron +++ ++ +0 +++ + + 0 115B 116 C + 0+1 e positron0e electron  rays Detectable-

63. 2 - 63 CH 104  rays  image Shows blood flow  rays  image Shows blood flow B 5 11 116 C0+1e + Positron Emission Tomography (PET)   Positron +++ ++ +0 +++ + + 0 0e electron  rays Detectable-  + 0+1 e electron gamma positron 0 e