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

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Chapter 28 Nuclear ChemistryNuclear RadiationNuclear TransformationsFission and FusionRadiation in Your LifeCh 28.1 Nuclear RadiationRadioactivityTypes of RadiationRadioactivityRadioisotopes 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 offRadioactivityMarie Curie (1867-1934) named the processProcess by which unstable atomic nuclei achieve stabilityWon Nobel Peace Prize 1903 along with Pierre Curie and Antoine Henri BecquerelRadiationPenetrating rays and particles emitted by a radioactive sourceTypes of RadiationAlphaBetaGammaAlphaHelium 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 skinBetaFast moving electrons formed by the decomposition of a neutronBeta Particles0-1e or Can be stopped by aluminum foil or pieces of woodGammaHigh energy electromagnetic radiationNo mass, no chargeCan almost be stopped by several feet of concrete or several inches of leadChernobylApril 26, 1986 at 1:23:44amReactor 4 explodedReleased 30-40 times the amount of radiation as bombing Japan didChapter 28.2 Nuclear TransformationsNuclear Stability and DecayHalf LifeTransmutation ReactionsNuclear 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)20682PbBeta Emissions6629Cu 6630Zn + 0-1e146C 147N + 0-1ePositronParticle with the mass of an electron, but a positive charge0+1e85B 84Be + 0+1eAlpha EmissionAll nuclei with an atomic number greater than 83 are radioactive20482Pb 20080Hg + 42He22688Ra 22286Rn + 42HeHalf LifeThe time required for one half of the nuclei of a radioisotope sample to decay to productsArtificial RadioisotopesUsually have very short half livesUsed in nuclear medicinePET Scan - Positron Emission Tomography Brain FunctionThyroid 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)

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