Ch. 25.1 Radiation

Brain storm With your elbow partner come up with any 5 facts, information or events that come to mind when you hear the term “Radioactivity”

What is Radiation? What is radioactivitity 3 min

Radioisotopes Elements larger than AN 83 Examples: Uranium, Plutonium…. Have unstable nuclei that breaks apart releasing radiation

What is Radiation? High rays of energy that can go through solid objects and cause damage

Alpha Beta 2 Classes of Radiation 1.Particle Rad. Gamma 2. Electromagnetic Waves 1.Particle Rad. High speed element fragments Alpha Beta Rays of energy Gamma

Evaluating the danger…. 1. What blocks/protects you from the radiation? 2. Rate the penetrating power?

Which radiation is most dangerous? look for yourself....

Discuss this with your elbow partner Why do most materials block alpha, beta but not gamma radiation?

Warm-up Go to your Cornell Notes (11). Look at the 3 questions you wrote in the Cornell space 1. Person a) asks the first Cornell question and Person b) answers it 2. Reverse roles: Person b) asks the question- don’t worry if you have the same question- answer them again! Do 3 times until done

Alpha (α) Particle Radiation Helium nucleus: 42He Rutherford’s gold foil experiment

Writing α Decay Rx MN: 272 → 268 + 4 = 272 √ AN: 92 → 90 + 2 = 92 √ 92272U _?_ + 42He 92272U 26890Th + 42He Law of Conservation of Mass! MN: 272 → 268 + 4 = 272 √ AN: 92 → 90 + 2 = 92 √

Practice α decay…. Neptunium-195 MN: 195 → 191 + 4 = 195 √ 93195Np → 91191Pa + 42He MN: 195 → 191 + 4 = 195 √ AN: 93 → 91 + 2 = 93 √

Beta (β) Particle Radiation A beta particle is a fast-moving electron Beta particle: o-1e

92270U β _?_ + o-1e 92270U β 27093 Np + o-1e Writing β Decay Rx Law of Conservation of Mass! MN: 270 → 270 + 0 = 270 √ AN: 92 → 93 - 1 = 92 √

93195Np → 19594 Pu + o-1e Practice beta decay Neptunium-195 MN: 195 → 195 + 0 = 195 √ AN: 93 → 94 - 1 = 93 √

HW Alpha and beta decay for Th-230 Pa-258 Plutonium-243

Gamma Radiation Gamma rays are high energy electromagnetic photons (similar to light rays, X-ray, UV) Have not mass, no Rx writing! Radioactive decay often produces alpha, beta and gamma radiation simultaneously!!!

Electromagnetic Spectrum

Reflection With a highlighter underline all new keywords Write 4 questions in the Cornel Space Make a Venn Diagram for alpha/beta and gamma radiation Write alpha and beta decay for Uranium-255