chapter 28 nuclear chemistry nuclear radiation nuclear transformations fission and fusion radiation...

Download Chapter 28 Nuclear Chemistry Nuclear Radiation Nuclear Transformations Fission and Fusion Radiation in Your Life

Post on 18-Jan-2016




0 download

Embed Size (px)


  • Chapter 28 Nuclear ChemistryNuclear RadiationNuclear TransformationsFission and FusionRadiation in Your Life

  • Ch 28.1 Nuclear RadiationRadioactivityTypes of Radiation

  • RadioactivityRadioisotopes an isotope that has an unstable atomic nucleus and undergoes radioactive decayAlways accompanied by large emissions of energyNot affected by temp., pressure, or catalystsCan not speed up or slow down the reaction or turn off

  • RadioactivityMarie Curie (1867-1934) named the processProcess by which unstable atomic nuclei achieve stabilityWon Nobel Peace Prize 1903 along with Pierre Curie and Antoine Henri Becquerel

  • RadiationPenetrating rays and particles emitted by a radioactive source

  • Types of RadiationAlphaBetaGamma

  • AlphaHelium nuclei emitted from a radioactive sourceAlpha particlesContain 2 protons and 2 neutrons and have a double positive charge42He or Can be stopped by a sheet of paper or your skin

  • BetaFast moving electrons formed by the decomposition of a neutronBeta Particles0-1e or Can be stopped by aluminum foil or pieces of wood

  • GammaHigh energy electromagnetic radiationNo mass, no chargeCan almost be stopped by several feet of concrete or several inches of lead

  • ChernobylApril 26, 1986 at 1:23:44amReactor 4 explodedReleased 30-40 times the amount of radiation as bombing Japan did

  • Chapter 28.2 Nuclear TransformationsNuclear Stability and DecayHalf LifeTransmutation Reactions

  • Nuclear Stability and Decay1500 different nuclei, only 264 are stableFor low atomic number (up to 20), the ratio of protons to neutrons is 1(ratio of stability)126C 147NAtomic numbers above 20, have a ratio of protons to neutrons of 1.5(ratio of stability)20682Pb

  • Beta Emissions6629Cu 6630Zn + 0-1e

    146C 147N + 0-1e

  • PositronParticle with the mass of an electron, but a positive charge0+1e

    85B 84Be + 0+1e

  • Alpha EmissionAll nuclei with an atomic number greater than 83 are radioactive

    20482Pb 20080Hg + 42He

    22688Ra 22286Rn + 42He

  • Half LifeThe time required for one half of the nuclei of a radioisotope sample to decay to products

  • Artificial RadioisotopesUsually have very short half livesUsed in nuclear medicine

  • PET Scan - Positron Emission Tomography

  • Brain Function

  • Thyroid TumorsDogIodine 131

  • Bone FracturesTechnetium

  • Radioactive Isotope UseC-14 Used to determine the age of biological remains (archaeology)I-131 Used to detect and cure hyperthyroidism (overactive thyroid)Co-60 Used as a source of radiation for radiotherapy of cancerTc-99m Used to image blood vessels, especially in the brain, to detect tumorsPu-239 Used as a highly fissionable fuel source for nuclear power or nuclear weaponsAm-241 Used in tiny amounts in smoke detectors as a source of ions to make a currentU-235 Used as fissionable fuel source for nuclear power or nuclear weaponsU-238 Used to determine the age of uranium-containing rock formations (geology)


View more >