1. ICP 10/2/12 Finish radioactivity

2. Warmup 1)Which particles are lightest: protons, neutrons, electrons? 2)Which particles are in the nucleus: protons, neutrons, electrons? 3)Write a nuclear symbol: 3 protons, 4 neutrons, 2 electrons

3. Agenda Fission/Fusion Notes Finish Lab Report (Centsium) / Check homework (Half-Life Problems) Go over answers to Half-Life Problems Tomorrow: Meet in computer lab with textbook and 1 st quarter test study guide.

4. What is fission? http://library.thinkquest.org/17940/texts/fission/fission.html

5. Why does the chain reaction work? http://library.thinkquest.org/17940/texts/fission/fission.html

6. C. Johannesson F ission splitting a nucleus into two or more smaller nuclei 1 g of 235 U = 3 tons of coal

7. Where does the energy in fission come from? 235U + 1 neutron  2 neutrons + 92Kr + 142Ba + ENERGY The energy was stored in the strong binding forces that held the uranium nucleus together.

8. Fission Chain Reactions An uncontrolled fission reaction results in a big explosion. Hiroshima! A controlled fission reaction will give nuclear power at a power plant.

9. C. Johannesson F ission

10. C. Johannesson Nuclear Power Fission Reactors Cooling Tower

11. C. Johannesson Nuclear Power Fission Reactors

12. Fusion Fusion occurs in the sun when four hydrogens are forced together by the energy of high temperature and high pressure. 4 Hydrogens  1 Helium. What bizarre thing happened? The protons changed to neutrons. This change releases energy, and this is why fusion produces energy. Fusion

13. C. Johannesson Mass Defect Difference between the mass of an atom and the mass of its individual particles. 4.00260 amu4.03298 amu