1. Bellwork 9-24-2014 1. What are 4 components required for a nuclear reactor to power a town (produce electricity)? **Tests will be returned Thu/Fri

2. Agenda Bellwork Build your own nuclear reactor Exit slip Homework

3. Nuclear Reactors You have the following materials at your disposal: Beaker of water Straw Hot plate Aluminum foil Windmill Cork if you need to stopper your windmill

4. Build it! Use your knowledge from the nuclear reactor video to build a nuclear reactor that will power your windmill! When you are done, answer the following questions about your reactor: 1. How did you make your nuclear reactor work? Give a description of how you built your device. 2. What specific components were needed to maximize efficiency?

5. Clean Up I will take the beaker off the hot plate with a hot hand Take out straws and leave on desk IF you used the tin foil, unwrap it for the next class Set everything back in the center when your are done CAUTION – HOT PLATES ARE STILL HOT!

6. Exit Slip Stamped questions from nuclear reactor building lab

7. Homework Reading on radiation Highlight important information Annotate: Each section – write a mini one sentence summary on the article itself next to the appropriate section 10 sentences total

8. Example First paragraph: Radioactivity is the emission of particles or from unstable atoms and can be natural or induced.

9. Bellwork 9-25-2014 Form your article: 1. What is radioactivity? 2. Describe alpha particle radiation. 3. What two main isotopes are released into the atmosphere from burning coal? **Pass back tests

10. Announcements Points – class monitor Extra credit drawing Tutoring Friday is ON!

11. Why is 36 Cl Unstable? Unstable

12. Nuclear Strong Force Mysterious force holding nucleus (protons and neutrons) together

13. Student Demo Everyone up! 4 students start in the center of the desks – this is our NUCLEUS Question: What happened when too many students were added to the “nucleus”

14. What makes an atom unstable? Nuclear strong force fails Too many neutrons or too many protons Stability is based on a specific ratio of protons to neutrons in the nucleus In nature, 92 p+ MAX  Uranium

15. Why do we call these atoms unstable? Atoms like 36 Cl are radioactive elements They break down or DECAY at a specific rate and give off RADIATION

16. Nuclear Radiation Nuclear radiation is the process during which the nucleus of an unstable atom spontaneously breaks down in an attempt to form a more stable nucleus. This process emits RADIATION

17. What is radiation? Waves traveling through space at specific wavelengths Examples: Natural radiation from the sun High energy radiation from space, air or the earth Background radiation – main source (alpha, beta, gamma)

18. Share with your neighbor Write down your answer 1. What is the nuclear strong force? 2. What types of atoms overcome this force? 3. What happens when atoms overcome this force?

19. Nuclear Decay The rate at which an element breaks down into a daughter element This is calculated using half lives t 1/2

20. Half life: how does it work? 1. What happened after the first half life? 2. What happened after the second?

21. Graphical form

22. Half Life The amount of time it takes for an element to decay to HALF of its original amount For example: Chlorine-36 will decay to half of its original amount in 301,000 years

23. How is it measured? Half life can be determined using any amount of the substance that can be measured: Mass – grams Protons Neutrons

24. Practice with a neighbor 1. 50 grams of Chlorine-36 has a half life of 301,000 years, how much will be left after 1 half life? 2. How much will be left after 2 half lives? **You will need a calculator!

25. Half Life Problem 1 200 grams of Bismoth-214 has a half life of 20 minutes. Fill in the table to determine how much is left after 4 half lives. Time passed (min)Half lifeAmount remaining (g) 00 1 2 3 4

26. Half Life Problem 2 After 135 days, you have 8 protons of Iron-59 left. This element has a half life of 45 days. How much did you start with? Time passed (min)Half lifeAmount remaining (P+) 00

27. On your own… Work on the half life problems on your worksheet independently This is partner work = voice level 2, if you are too chatty you will be moved or asked to leave. You have 20 minutes to complete this for a stamp

28. Exit Slip 9-25-2014 Describe WHY elements have half lives and WHAT half life is in your own words using key vocabulary from today: The WHY:The WHAT: Nuclear strong force - Radioactive elements Radioactivity - Half Radiation - Decay Unstable - P+, n 0, mass Isotopes

29. Work Collection Bellwork separate 1. Nuclear reactor video questions 2. Exit slip – questions from nuclear reactor lab 3. Radioactivity article 4. Lab sheet from today 5. Exit slip from today

30. Bellwork 9-30-2014 1. What types of atoms decay according to their half lives? What do they give off during this process? 2. If 130 grams of radioactive Carbon-14 has a half life of 5,730 years, how much will be left after 3 half lives? How much time has passed? Time passed (min)Half lifeAmount remaining (g) 00 1 2 3

31. Homework Answers 1 = 25g left 2 = 25 p+ left 3 = 75 n left 4 = started with 64 g

32. Announcements Volunteers? Class ambassador Class monitor Class tutors Test corrections due next Mon/Tue, Oct 6/7 Tests have been posted online If you missed the test you will be required to do test corrections for the whole test in order to raise your 0 to a 3.

33. Test Correction Reminder FOR EACH QUESTION YOU GOT WRONG: 1. EXPLAIN: why you got the question wrong 2. WRITE: the correct answer or solution 3. EXPLAIN: why that answer is correct

34. Half Life Activity Period 2, 4, 5(graph) In groups of 4 – you will need a paper plate and a lab sheet 1. Follow the procedures on your lab sheet 2. Graph your data using appropriate graph labels: a. Title b. X and Y axis labels c. Appropriate scale 3. You have 20 minutes to complete for a stamp

35. Honors: Another way… Half life can also be calculated using an equation: A = A 0 (1/2) t/h A = amount remaining A 0 = initial amount t = time h = half life of the isotope

36. Oder of surgeries… I mean operations… 4 easy steps: Step 1: Plug in the numbers Step 2: divide the exponent **Exponent values must ALWAYS be in the same units Step 3: raise ½ to the power (quotient of step 1) Step 4: Multiply

37. Do it… Example 1: 50 grams of Bismoth-214 has a half life of 20 minutes. Use the equation to determine how much is left after 200 minutes. A = A 0 (1/2) t/h A = 50 (1/2) 200/20 A = 50 (1/2) 10 A = 50 (0.00097) A = 0.05 g

38. Honors: Practice Problems Do the first 2 practice problems from the worksheet on separate sheet of paper (homework).

39. Objective: Students will be able to create and write balanced chemical equations for alpha, beta and gamma decay. http://www.youtube.com/watch?v=Zw0pHT4 7AAU

40. What is a balanced equation? In terms of radioactive decay: Both sides of the equation arrow have the same TOTAL mass and number of protons.

41. Interesting Fact Alpha, beta and gamma decay are responsible for supplying HALF of the Earth’s natural heat

42. Alpha Decay Alpha decay is one of the ways unstable elements emit radiation in an attempt to become more stable

43. Alpha Decay Simulation On your worksheet is the website you will visit for this simulation Complete ONE worksheet per pair You have 20 minutes

44. Alpha Decay – Exit Slip 5 minutes: In your notes: Describe alpha decay. On a half sheet of paper 1. What element is emitted and what subatomic particles does it consist of? Helium – 2p+ and 2n 0 2. How do you determine the new element produced? Subtract 2 protons (move two to the left on the periodic table) 3. Give an example: Write the alpha decay of Uranium – 235. Uranium-235  _____________ + _______________ 235 92  _________ + _________ U Thorium – 231 Helium - 4 231 90 Th 4 2 He 231 90 Th

45. Bellwork: Honors 8-1-2014 Use the half life decay equation to solve the following problem: A = A 0 (1/2) t/h 1. Thorium-228 has a half life of 1.9 years. How much Thorium did you START with if only 3 grams remain after 38 years? 2. Thorium-234  ___________ + _____________ Th  ________ + ________ 234 90

46. Bellwork 8-1-2014 1. Complete the following equation using alpha decay in HYPHEN notation and SYMBOL notation Thorium-234  ___________ + _____________ Th  ________ + ________ 2. Period 6: Use the product from alpha decay in the pervious reaction and put it through beta decay (Hint: not the helium atom!) __________  ___________ + ____________ 234 90

47. Announcements Test corrections due next Mon/Tue I am allowing everyone to correct the first test but in the future I will not giving credit to students who do test corrects with a formative grade <2.7 Grade are posted on the back wall – check as you leave I will be holding individual conferences with students today while you work Homework quizzes

48. Agenda Bellwork (10 minutes) Beta Decay (20 minutes total) Beta Decay debrief (5 minutes) Gamma Decay notes (10 minutes) Exit slip – review all three types of decay (5 minutes) If time – posters on one form of decay to display in the room (extra credit)

49. Beta Decay Beta decay is another way that unstable elements emit radiation in an attempt to become more stable

50. Beta Decay Simulation On the backside of your worksheet is the website you will visit for this simulation Complete ONE worksheet per pair You have 20 minutes

51. Beta Decay – Debrief 5 minutes: In your notes: Describe beta decay. 1. What particles are emitted during this type of decay? 2. A _________ changes into a ____________. 3. How do you determine the new element produced? 4. Give an example: Write the beta decay of Uranium – 235. Uranium-235  _____________ + _______________ 235 92  _________ + _________ U

52. Gamma Decay Gamma decay is the last Form of decay we will talk about where unstable atoms emit waves in an attempt to become more stable.

53. No simulation  Gamma Decay: https://www.youtube.com/watch?v=5U3YVW8Fk-M In your notes: Describe gamma decay. What is given off and how do you determine the stable element produced? 1. Give an example: Write the gamma decay of Uranium – 235. Uranium-235  _____________ + _______________ 235 92  _________ + _________

54. With a partner… Make a poster of your own rendition of alpha, beta or gamma decay that would be easy to understand by someone who has NEVER learned the subject. Include: What is emitted and what it consists of How mass and # of protons change How you determine the new element produced An example of the decay used in an equation (HINT: this can be used to hit the other points)

55. Homework 8-1-2014 Finish the packet on alpha, beta and gamma decay by Thursday/Friday Homework quiz Thu/Fri – bellwork

56. Exit Slip 8-1-2014 Fill in the blanks: 1. Alpha decay radiation emits an ________ particle that is also called _________. This element consists of ____ protons and ____ neutrons. The daughter element produced has _____ less protons and its mass is reduced by ______. 2. Beta decay radiation emits an ________ with a mass of ______ and a atomic (proton) number of ________. A _______ is changed into a __________ in the process. The daughter element produced has ______ more proton and the ________ mass. 3. Gamma decay radiation emits __________ that have a mass of _____ and _____ protons. The daughter element produced is ______.