際際滷

際際滷Share a Scribd company logo

Nuclear stability

Download as PPT, PDF
Z
zehnerm2

This document discusses nuclear stability and radioactive decay. It defines three types of radiation - alpha, beta, and gamma - and their properties. It provides examples of alpha and beta decay nuclear equations. The document also explains mass defect, which is the difference between the calculated mass of a nucleus' protons and neutrons and its experimentally measured mass. This mass defect is released as energy during nuclear reactions according to the mass-energy equivalence formula E=mc2.

1 of 7
Downloaded 39 times
Nuclear Stability Nuclear reactions change the composition of an atoms nucleus Radiation is produced by nuclear reactions Only a few atoms in nature are radioactive (have unstable nucleus)
Types of Radiation Name Identity Charge Penetrating Ability Alpha 2 protons, 2 neutrons 2+ Low, stopped by paper Beta Electrons 1- Medium, stopped by heavy clothing Gamma High energy non-particle radiation None High, stopped by lead
Radioactive Decay When an atom emits radiation (because original nucleus decomposes to form a new nucleus) Emitting alpha radiation: 226 88Ra 222 86Rn + 4 2留 (see p. 115)
Write the nuclear equation for the alpha decay of gold-185 185 79 Au M ZX + 4 2留 185 = M + 4 M = 181 79=Z+2 Z=77 185 79 Au 181 77Ir + 4 2留
Write a nuclear equation for the beta decay of Sodium-24 24 11Na 24 12Mg + 0 -1 24 11Na Z AE+ 0 -1 24 11Na ? + 0 -1
Mass Defect The difference between the unbound system calculated mass and experimentally measured mass of nucleus. It can be calculated: (sum of masses of protons and neutrons) - (actual measured mass of nucleus) This mass defect is released as energy according to the relation E = mc2 http://antoine.frostburg.edu/chem/senese/101/atoms/slides/img019.GIF
Mass Defect The difference between the unbound system calculated mass and experimentally measured mass of nucleus. It can be calculated: (sum of masses of protons and neutrons) - (actual measured mass of nucleus) This mass defect is released as energy according to the relation E = mc2 http://antoine.frostburg.edu/chem/senese/101/atoms/slides/img019.GIF

More Related Content

Nuclear stability

  • 1. Nuclear Stability Nuclear reactions change the composition of an atoms nucleus Radiation is produced by nuclear reactions Only a few atoms in nature are radioactive (have unstable nucleus)
  • 2. Types of Radiation Name Identity Charge Penetrating Ability Alpha 2 protons, 2 neutrons 2+ Low, stopped by paper Beta Electrons 1- Medium, stopped by heavy clothing Gamma High energy non-particle radiation None High, stopped by lead
  • 3. Radioactive Decay When an atom emits radiation (because original nucleus decomposes to form a new nucleus) Emitting alpha radiation: 226 88Ra 222 86Rn + 4 2留 (see p. 115)
  • 4. Write the nuclear equation for the alpha decay of gold-185 185 79 Au M ZX + 4 2留 185 = M + 4 M = 181 79=Z+2 Z=77 185 79 Au 181 77Ir + 4 2留
  • 5. Write a nuclear equation for the beta decay of Sodium-24 24 11Na 24 12Mg + 0 -1 24 11Na Z AE+ 0 -1 24 11Na ? + 0 -1
  • 6. Mass Defect The difference between the unbound system calculated mass and experimentally measured mass of nucleus. It can be calculated: (sum of masses of protons and neutrons) - (actual measured mass of nucleus) This mass defect is released as energy according to the relation E = mc2 http://antoine.frostburg.edu/chem/senese/101/atoms/slides/img019.GIF
  • 7. Mass Defect The difference between the unbound system calculated mass and experimentally measured mass of nucleus. It can be calculated: (sum of masses of protons and neutrons) - (actual measured mass of nucleus) This mass defect is released as energy according to the relation E = mc2 http://antoine.frostburg.edu/chem/senese/101/atoms/slides/img019.GIF