2. Catalyst What happens when you change the number of electrons in an atom? What happens when you change the number of protons in an atom? What happens when you change the number of neutrons in an atom? End

4. LESSON 2.5 – NUCLEAR CHEMISTRY: FISSION, FUSION, and RADIOACTIVITY

5. Today’s Learning Targets LT 2.11 – I can explain the forces that exist within the nucleus of an atom. I can compare the strength of the nuclear force to other (electromagnetic, gravity, etc) forces that exist. LT 2.12 – I can explain why energy is released in a nuclear fusion/fission reaction and I can calculate the amount of energy released.

6. Today’s Focus Question What is nuclear energy?

7. What are forces?

8. I. Forces A force is a push or pull 4 fundamental forces in the universe 1.Gravity 2.Coulombic Force 3.Strong Nuclear Force 4.Weak Nuclear Force

9. What are the fundamental forces?

10. I. We Have a Problem The nucleus of an atom contains many positive changes (protons) If the nucleus contains a bunch of positive charges, why doesn’t the nucleus of the atom split apart?

11. II. Strong Nuclear Force The strong nuclear force is the force that exists between particles in the nucleus of an atom Much stronger then coulombic forces, so the attraction between particles in nucleus is much stronger then the proton repulsion

12. III. Weak Nuclear Forces The weak nuclear force is the force that allows certain elements to become radioactive.

13. Strength of the Forces Strong Nuclear Force Electromagnetic Force Weak Nuclear Force Gravitational Force Weakest Force Strongest Force

14. SUMMARIZE Use the following terms in your summary: Force Gravitational Electromagnetic Strong Weak

15. What are nuclear fusion and fission?

16. I. Nuclear Fusion Fusion – When two things combine into one Nuclear fusion is when two atomic nuclei fuse into one new, HEAVIER, atom

18. II. Nuclear Fission Fission – Splitting of an item into two Nuclear fission is when a very heavy nucleus splits into two smaller, more stable nucleuses

20. SUMMARIZE Use the following terms in your summary: Fission Fusion Strong Nuclear Force

21. LESSON 2.5 – ISOTOPES AND RADIOACTIVE DECAY

22. Today’s Learning Targets LT 2.13 – I can compare and contrast normal isotopes and radioactive isotopes. I can discuss the three forms of decay that radioactive isotopes can undergo and how the nucleus is altered in each type of decay. LT 2.14 – I can list the three different type of radiation and the impact that each one of these types of decay can have on myself and other living matter

23. What are isotopes?

24. I. Isotopes Isotope – Atoms of the same element have different numbers of neutrons and thus have different atomic masses.

29. What is radioactive decay?

30. I. Radioactive Decay Atoms can be unstable and breakdown Radioactive Decay – The spontaneous breakdown of the nucleus into a smaller nucleus, accompanied by the release of particles, radiation, or both.

31. What are the 3 types of radioactive decay?

32. I. Alpha (α) Decay Alpha Decay – When an atom splits its nucleus into: 1.A smaller nucleus and 2.A Helium atom (2 protons, 2 neutrons). Observed often in very heavy atoms Alpha particles on travel a few cm in air Paper blocks alpha particles

34. Alpha Radiation

35. II. Beta (β) Decay Some elements are unstable because their proton to neutron ratio is too large. Beta decay converts neutrons to protons and releases an electron known as a beta particle neutron  proton + β Travel a few meters in the air Metals provide a shield against beta radiation. Electron

37. Beta Radiation

38. III. Gamma (γ) Decay Gamma rays are high energy waves that are released when nucleus goes from high energy state to low energy. Gamma radiation is the most dangerous. It can lead to DNA mutations and cancers. Gamma radiation requires thick pieces of lead/concrete in order to stop.

40. Gamma Radiation

41. Radiation Summary Type of RadiationDescriptionBlocked by? Alpha (α) Beta (β) Gamma (γ) The spitting of a nucleus into a smaller nucleus and a He atom (alpha particle Converts a neutron to a proton and an electron (beta particle) High energy waves that are released by nucleus Blocked by paper Blocked by metals Blocked by lead

42. Class Example Label the following decay as alpha, beta or gamma decay 43 19 K  43 20 Ca + electron

43. Table Talk Label the following decay as alpha, beta or gamma decay 210 84 Po  206 82 Pb + 4 2 He

44. Table Talk Complete the following reaction if it undergoes beta decay: 14 7 N  ______ + _______

45. SUMMARIZE Use the following terms in your summary: Alpha Beta Gamma Decay Radioactive

46. Work Time Work on Practice for the next 10 minutes.

47. Online Simulator Please open the two simulators on the computer and complete the simulator handout with a partner.

48. Learning Target Log Assessment Rate your current level of understanding of LT 9.3 and 9.4. Rate yourself 1 – 4.

49. Exit Slip 1. What is fusion? 2. What is gamma decay? What will stop gamma radiation? 3. What type of decay is shown below: 231 91 Pa  227 89 Ac + 4 2 He

50. Exit Ticket 1. What is a force? 2. How does the strong nuclear force allow for the nucleus of an atom to remain together? 3. Rank the 4 fundamental forces from weakest to strongest.

51. Learning Target Log Assessment Rate your current level of understanding of LT 9.3 and 9.4. Rate yourself 1 – 4.

54. Homework Closing Time