Unit 7

1. Unit 7 Nuclear Chemistry By Kevin “KG” Gerber Ding and Steven “The Flash” Houg

2. Radioactive Decay • α-particle • β -particle • γ-ray

3. The Alpha Particle • α or He • Largest of the 3 radioactive particles • Lowest penetrating ability • Sample Decay: U α + Th 4 2 4 2 235 92 231 90 4 2

4. The Beta Particle e β • or • Same electrical charge and mass as an electron • Sample Decay: N O + e 0 -1 0 -1 13 7 13 8 0 -1

5. Gamma Rays • Y • Gamma rays are photons • They have no mass and no charge 00

6. Positron Emission e β 0 +1 0 +1 • or • Positrons are equivalent to positively charged electrons or positively charged beta particles • Formed when a neutron splits into a neutron and another particle (positron) p e + n 1 1 0 +1 1 0

7. Electron Capture • Occurs when an electron is captured by the nucleus e + p n 0 -1 1 0 1 +1

8. Radioactive Decay Series α + U Th 4 2 238 92 234 90 β + Th 0 -1 Pa 234 90 234 91 β + Pa U 0 -1 234 91 234 92 α + U Th 4 2 230 90 234 92

9. Half Life Equation • N=N0e-kt • K= ln 2 T1/2

11. Theory of Relativity • ∆E= (∆m)c2 • C is the speed of light (2.9*108 m/s2) • m is mass (kg) • E is energy (Joules)