nuclear chemistry. radioactive decay spontaneous breakdown of an atom’s nucleus breakdown results...
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Nuclear Chemistry
Radioactive DecaySpontaneous breakdown of an atom’s nucleus
Breakdown results in a lighter nucleus
Emits electromagnetic radiationNuclear radiation—radiation emitted from nucleus
Radioactive nuclide– nucleus that goes through radioactive decay, unstable. (Ex. Uranium
Types of Radioactive Decay1) Alpha particle (α)
Consists of 2 protons, 2 neutrons emitted during decay Helium nucleus ( 2
4He )—how particle represented
Can be stopped by paper, low energy Atomic number goes down 2, atomic mass goes down 4. Equation: 84
210 Po 82206 Pb + 2
4 He
2) Beta particle (β) Electron given off during radioactive decay Can be stopped by lead or glass Increase in atomic # Equation: 6
14 C 714 N + -1
0 β
3) Gamma Rays Has the most energy, only stopped by lead Ex. X-Rays
Example 1: Nuclear equation when an alpha particle emitted by 210
84Po
Example 2:Nuclear equation when a beta particle emitted by 210
82Pb
Practice: Alpha Decay
1) Be-9
2) U-238
3) Eu-154
Beta Decay
4) Th-234
5) K-43
Half-Life
Time period required for half of a radioactive nuclide to decay.
Vary depending on the nuclide, unique for each nuclide.
Ex. 146C has a half-life of 5715. Therefore, if we
have 10g of 146C, in 5715 years we will have 5g.
Half-Life Equation
AE = AO * 0.5 t/t(1/2)
AE = Substance amount
A0 = Initial substance amount
t = time elapsed
t1/2 = half-life
Example 1: Plutonium-239 has a half life of 24,110 years. We have 100g of this substance. How many grams will we have after 96,440 years?
More on Nuclear Chemistry
Nuclear Fission
Nuclear reaction where nuclei are SPLIT
Nucleus is broken down into a more stable nucleus.
HUGE amount of energy is released
Critical mass = minimum number of nuclei that can provide enough neutrons to maintain chain reaction.
Nuclear reactors = controlled fission reactions.
**Can induce a nuclear chain reaction!!!
Nuclear Reactors
Location where controlled fission reactions occur
Fuel rods in the core contain enriched uranium
Steam generation steam turbine electric generator
Control rods take in neutrons so fission is controlled
Production of radioactive waste
A TON of water is used to cool the reactors
Nuclear FusionNuclei having a light mass are joined.
Combination of light nucleiCreates heavy nucleus
Results in larger, stable nucleus.
MORE energy released than in nuclear fission !!!
Hard to control
Initiated by fission reaction (fission bomb) ---- H bomb
**Type of reaction happening in the sun and stars.
-fuel: hydrogen atom
cu
Applications to Nuclear Radiation
1) Radioactive DatingAge determination of artifact based on presence of
radioactive nuclide
2) Medical PurposesCancer treatmentsRadioactive tracers
3) Food ProcessingMeat exposed to radiationKills microorganisms
Prompt
We talked about nuclear energy today. Do you support or disagree with this type of green energy? Support your answer.
How could we harness the nuclear energy in the sun? Discuss how we might use nuclear fusion to benefit us.
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