1. Wed/Thurs Sept 17-18 Objective: Predict what an element will decay into. Checkpoint: Homework: Half-life / Nuclear decay wksht (due Friday)

2. Is Nuclear Technology Worth It? Source A: Radium Girls (due Tues)

3. Make a gmail account and sign in (gmail.google.com)

4. docs.google.com

6. Here is a copy of the graphic organizer http://goo.gl/tJ156r

7. Nuclear Chemistry When one element turns into another element

8. Band of Stability

9. Radioactive Decay

11. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days.

12. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 8 days

13. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 16 days

14. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 24 days

15. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 32 days

16. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 40 days

17. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of Iodine-131 is 8 days. 48 days

18. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years.

19. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 4.46 billion years

20. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 8.92 billion years

21. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 13.38 billion years

22. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 17.84 billion years

23. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 22.3 billion years

24. Half-Life The time it takes for half of a radioactive sample to decay. The half-life of radioactive Uranium-238 is 4.46 billion years. 26.76 billion years

25. Cobalt–89 has a half–life of 9 years. How much of the substance would remain after 3 half–lives? (%) 100% 50% 1 half life (9 years) 25% 2 half lives (18 years) 12.5% 3 half lives (27 years)

26. Radon–222 has a half life of 3.2 days. How much radon–222 will remain after 9.6 days if you started with a 3.0 mg sample? 3.0 mg 1.5 mg 1 half life (3.2 days) 0.75 mg 2 half lives (6.4 days) 0.375 mg 3 half lives (9.6 days)

27. The decay of cesium-137 has a half-life of 30 years. Approximately how many years must pass to reduce a 25 mg sample of cesium 137 to 8.7 mg? 25 mg 12.5 mg 1 half life (30 years) 6.25 mg 2 half lives (60 years) Between 30-60 years, so approximately 50 years 8.7 mg

28. Types of Radiation Ionizing Radiation (can cause health problems) Non-ionizing Radiation (does not impact health) Electromagnetic Radiation Nuclear Radiation

31. My NotesYour Notes

32. Nuclear Notation: Subatomic Particles p 1 1 proton n 1 0 e 0 e 0 1 neutron electron positron

33. All elements after Bismuth (#83) are unstable Wrong proton/neutron ration

34. Write Bismuth in nuclear notation How many protons & neutrons? Bi 209 8383 protons 209 – 83 = 126 neutrons

35. U 283 92 He 4 2 Th 279 90 Th 230 90 He 4 2 Ra 226 88

36. Pu 239 94 He 4 2 U 235 92 Np 237 93 He 4 2 Pa 233 91

37. K 40 19 e 0 Ca 40 20 Bi 214 83 e 0 Po 214 84 Beta decay: Too many neutrons, not enough protons Solution: Get rid of an electron

38. N 13 7 e 0 1 C 6 C 11 6 e 0 1 B 5 Positron Emission: Too many protons, not enough neutrons Solution: Get rid of a positron

39. Cr 51 24 e 0 V 51 23 Electron Capture: Too many protons, not enough neutrons Solution: Capture an electron from electron cloud to nucleus Hg 201 80 e 0 Au 201 79

40. Pb* 206 82 0 0 Pb 206 82 Gamma Decay: Too much energy Solution: Release energy in form of a gamma ray Hg* 201 80 0 0 Hg 201 80

42. Thought of the Week I don’t believe you have to be better than everybody else. I believe you have to be better than you ever thought you could be. (Ken Venturi)