1 / 14

Nuclear Chemistry

Nuclear Chemistry. Chapter 18. Quick Review. Mass # Symbol Element Name or symbol – Mass # Parts of a Reaction Reactants  Products. Types of Radiation. Alpha emission or decay ( a ) –helium atom 4 2 He 238 92 U  4 2 He + 234 90 Th

elwyn
Télécharger la présentation

Nuclear Chemistry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nuclear Chemistry Chapter 18

  2. Quick Review • Mass # Symbol • Element Name or symbol – Mass # • Parts of a Reaction Reactants  Products

  3. Types of Radiation • Alpha emission or decay (a) –helium atom 42He • 23892U  42He + 23490Th • Beta emission or decay (b)– 0-1e in the products • 23490Th  23491Pa + 0-1e • Gamma emission or decay (g) - 00g • 23892U  42He + 23490Th + 00g

  4. Types of Radiation & Particles • Positron emission or decay - 0+1e • 2211Na  0+1e + 2210Ne • Electron capture – beta particle in the reactants • 20180Hg + 0-1e  + 20179Au • Neutron emission or decay– 10n • 20984Po 10n + 20084Po • Proton – 11H or 11p

  5. Balancing Nuclear Equations • Mass # and the atomic # totals must be the same for reactants and the products. • 3919K  3517Cl + ___ • 20682Pb  0-1e + ___ • 23894Pu + ___ 42He + 23592U

  6. Writing Balanced Nuclear Equations • Alpha decay of Cu-68 • Gamma emission of Thorium-235 • Positron emission of P-18 • Astatine-210 releasing 3 neutrons • Electron capture of Ti-45

  7. Half-Life and Nuclear Stability • Radioactive isotopes or nuclides all decay because they are unstable, some just breakdown much faster than others • Half-life – amount of time for half of the original sample to decay • For two samples of the same isotope, regardless of the sample size, after one half-life, only half of the original amount of sample remains.

  8. Sample Half-lives • IsotopesHalf-Live • Carbon – 14 5730 years • Sodium – 24 15 hours • Bismuth – 212 60.5 seconds • Polonium – 215 0.0018 seconds • Thorium – 230 75400 years • Thorium – 234 24.1 days • Uranium – 235 7.0 x 108 years • Uranium – 238 4.46 x 109 years

  9. Half-life sample problems • Barium – 139 has a half-life of 86 minutes. If you originally have a 10 gram sample of Barium-139, how much will be left after 258 minutes?

  10. Half-life sample problems • How many days will it take 50 grams of Radon – 222 (half-life of 3.82 days) to decay to 3.125 grams?

  11. Half-life sample problems • If a sample of Cesium-135 decays from 10 grams to 2.5 grams over a period of 84 days, what is the half-life of Cesium-135?

  12. Fission versus Fusion • Fusion – combining two smaller nuclei into one heavier, more stable nucleus. 32He + 11H  42He + 01e • Fission – splitting a large unstable nucleus into two nuclei with smaller mass numbers. 20984Po 12552Te + 8432Ge

  13. Sample fission reaction

  14. Sample fusion reaction

More Related