2. 6 Days Until the Benchmark Catalyst: 1.What material stops beta decay? 2. Label the following decay as alpha, beta or gamma decay 210 84 Po  206 82 Pb + 4 2 He End

6. Today’s Learning Targets LT 9.2 – I can explain why energy is released in a nuclear fusion/fission reaction and I can calculate the amount of energy released.

7. Today’s Focus Question Why has E=mc 2 changed the world?

8. Conservation of Matter Matter cannot be created or destroyed, it can only change forms. When compounds react the mass of the atom is not the same as the mass of protons and neutrons alone. Mass Defect – The difference between the atom and what it should weigh as protons, neutrons, and electrons.

9. Mass is Converted to Energy! The mass of a compound tells us the amount of energy that it has. Matter can be turned into energy and energy can be turned into matter Einstein’s equation allows us to calculate the amount of energy that would be released if mass is lost

10. The Equation E = energy (measured in Joules) m = mass (measured in kilograms) c = the speed of light, 3.0 x 10 8 m/s or 300,000,000

11. Class Example You have a 2 kg object. Calculate the amount of energy that would be produced if you were to convert all of this mass into energy. (c = 3.0 x 10 8 )

12. Table Talk You have a 5 kg substance. How much energy would be produced if this mass was converted to energy? (c = 3.0 x 10 8 )

13. Stop and Jot If you produced 500,000 J of energy when you converted the mass of a substance to energy, then what was the original mass of the substance? (c = 3.0 x 10 8 )

14. Applications of E=mc 2 If we know the energy associated with the loss of mater in the nucleus, then we can use this energy for both good and bad. Common examples: –Nuclear energy –Atomic Bomb –Smoke detectors –Radio-isotopes in medicine

15. SUMMARIZE

16. Around the World Find a partner that matches the number you were given. Get a white board and marker. You are going to race the other teams to get through the 8 questions around the room. You need to alternate who does the problems otherwise you will be forced to stop for 1 minute.

18. Homework 9.2 due Monday Closing Time