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Download Nuclear Chemistry “Nuclear Reaction” – Anytime the nucleus of an atom changes. Nuclear Chemistry

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  • Nuclear ChemistryNuclear Reaction Anytime the nucleus of an atom changes.Nuclear Chemistry

  • Types of Nuclear Reactions:FissionFusionRadioactive Decay

  • Radioactive DecayNucleus

  • FissionThe splitting apart of a large atom (nucleus) into two smaller atoms

  • FusionThe combining of two small atoms to produce a single larger atom

  • So Whats the Point?The products of a fission and a fusion reaction weigh less than the reactants.In other words, matter disappears!Where does the matter go?It turns into energy! According to the equation: E = mc2The point is You get a poop load of energy!

  • FissionThe splitting apart of a large atom (nucleus) into two smaller atoms

  • Chain Reaction

  • Critical MassWhen a hunk of fissionable material can keep reacting on its own

  • Critical MassWhen a hunk of fissionable material can keep reacting on its ownMost neutrons end up leaving the solid before they can hit another nucleus.

  • Critical MassWhen a hunk of fissionable material can keep reacting on its ownThick Hunk = Chain Reaction!

  • The Louis Slotin Accident On May 21, 1946, Louis Slotin and seven other colleagues performed an experiment that involved the creation of one of the first steps of a fission reaction by placing two half-spheres of beryllium (a neutron reflector) around a plutonium core. The experiment used the same 6.2-kilogram (13.7lb) plutonium core that had earlier irradiated Daghlian, later called the "Demon core" for its role in the two accidents. Slotin grasped the upper beryllium hemisphere with his left hand through a thumb hole at the top while he maintained the separation of the half-spheres using the blade of a screwdriver with his right hand, having removed the shims normally used. Using a screwdriver was not normal part of the experimental protocol. At 3:20 p.m., the screwdriver slipped and the upper beryllium hemisphere fell, causing a "prompt critical" reaction and a burst of hard radiation. At the time, the scientists in the room observed the "blue glow" of air ionization and felt a "heat wave". In addition, Slotin experienced a sour taste in his mouth and an intense burning sensation in his left hand. Slotin instinctively jerked his left hand upward, lifting the upper beryllium hemisphere and dropping it to the floor, ending the reaction. However, he had already been exposed to a lethal dose of neutron and gamma radiation. "As soon as Slotin left the building, he vomited, a common reaction from exposure to extremely intense ionizing radiation" recorded Dr Thomas D. Brock. Slotin's colleagues rushed him to the hospital, but irreversible damage had already been done. His parents were informed of their son's inevitable death and a number of volunteers donated blood for transfusions, but the efforts proved futile. Louis Slotin died nine days later on May 30, in the presence of his parents. He was buried in Winnipeg on June 2, 1946.

  • Critical Mass (Abombs)When a hunk of fissionable material can keep reacting on its own

  • The Hiroshima Bomb - Due to its long, thin shape, the Hiroshima bomb was called Little Boy. The material used was uranium 235. It is believed that the fission of slightly less than one kilogram of uranium 235 released energy equivalent to approximately 15,000 tons of TNT The Nagasaki Bomb - Compared to the one used on Hiroshima, the Nagasaki bomb was rounder and fatter. It was called "Fat Man." The material used was plutonium 239. The fission of slightly more than one kilogram of plutonium 239 is thought to have released destructive energy equivalent to about 21,000 tons of TNT.

  • Hydrogen Bomb50 Million tons TNTFission of PuFusion of H

  • Why are some atoms radioactive?

  • Why are some atoms radioactive?1) They dont have the proper ratio of protons to neutrons.

  • Why does it end here?(atomic number 83)

  • yellow = protons (+)orange = neutronsA NucleusWhat do like charges do?Why dont the protons fly apart?There has to be a stronger force inside the nucleus holding them together!Strong Nuclear ForceElectrostatic Force

  • Strong Nuclear ForceThe strong nuclear force is the strongest of all the forces of nature.Weak Nuclear ForceElectrostatic ForceGravityButIt only works over VERY small distances!

  • pink = protons (+)grey = neutronsA BIG NucleusBecomes ineffective at a distance that is equal the diameter of a Bismuth nucleus.Strong Nuclear Forcetoo far apart

  • pink = protons (+)grey = neutronsA BIG NucleusBecomes ineffective at a distance that is equal the diameter of a Bismuth nucleus.Strong Nuclear Forcetoo far apartSo the electrostatic force takes over.Alpha Decayhigh speed ejection

  • Why are some atoms radioactive?1) They dont have the proper ratio of protons to neutrons.2) They are too big.

  • Alpha Decay emits a helium nucleus loses 2 protons and 2 neutronsBeta Decay emits an electron neutron turns into a proton Electron Capture absorbs an electron proton turns into a neutron

  • Radioactive Decay

  • Nuclear Radiation

  • Radiation Nuclear vs Electromagnetic