1. From Isotopes to the sun…

2. The structure of the atom A=P=E Isotopes Isotopic notation

3. Radioactivity is known as the process in which an unstable nucleus changes by emitting particles or releasing energy. Unstable if too many protons or neutrons Two things can be emitted from the nucleus: Proton – Changes into a different element Neutron – more to come… The particle or energy given off is the source of radiation

4. Alpha (α) Beta (β) Gamma (γ)

5. Alpha particles Positively charged. Most massive type of radiation. Remove protons from the nucleus. Contains 2 protons and 2 neutrons…just like a Helium atom.

6. Gives up two protons and two neutrons. The element before the decay is like a reactant and is written on the left side of the arrow. The new nucleus and the particle given off is the product and is written on the right side of the arrow

7. Negatively charged. Adds a proton to the nucleus. HOW?? Because a neutron splits. HOW??? Electrons don’t belong in the nucleus….

8. A neutron splits into a proton and an electron. The electron does not belong in the nucleus so it shoots out! The mass number does not change Atomic number increases by one.

9. Do not have a charge and are not made of matter. Cause damage because of high energy. Great danger to health High energy waves

12. Half-life: The time it takes for half of a radioactive substance to decay. After 1 half life… ½ of the substance is gone… After 2 half lives… Another ½ is gone… But remember… Matter is neither created nor destroyed… In this instance… it decays to another form…

13. The graph below shows a typical decay curve for The count rate halves every 15 hours. So we say its half life is 15 hours.

14. Starting at a count rate of 400, the time for this to half to 200 is indicated by the first horizontal pink line: 15 hours. This can also be checked for going from 200 to 100: 15 hours.

15. Carbon-14 Dating!!! Carbon-14 Dating

16. What holds the nucleus together? The strong nuclear force And what causes the nucleus to become unstable and begin decay? Too many protons or neutrons Now lets look at fission vs. fusion…

17. The process in which a nucleus splits into 2 or more smaller fragments releasing neutrons and releasing a lot of energy! Nuclear Power plants use fission… So does the atomic bomb!!!

18. The process in which a light nucleus combines into a heavier nucleus and releases energy. Fusion is responsible for all elements higher than helium. Fusion takes place in the sun Click me for a cool video…