Skip to main content
Chemistry LibreTexts

7: Nuclear Chemistry

  • Page ID
    • 7.1: Nuclear Reactions
      Nuclear reactions are very different from chemical reactions. In chemical reactions, atoms become more stable by participating in a transfer of electrons or by sharing electrons with other atoms. In nuclear reactions, it is the nucleus of the atom that gains stability by undergoing a change of some kind. The energies that are released in nuclear reactions are many orders of magnitude greater than the energies involved in chemical reactions.
    • 7.2: Stable and Unstable Isotopes
      Many elements have at least one isotope whose atomic nucleus is stable indefinitely, but all elements have isotopes that are unstable and decay, at measurable rates by emitting radiation. Some elements have no stable isotopes and eventually decay to other elements. In contrast to the chemical reactions that were the main focus of earlier chapters and are due to changes in the arrangements of the valence electrons of atoms, the nuclear decay results in changes within atomic nuclei.
    • 7.3: Spontaneous Nuclear Decay
      Unstable nuclei spontaneously emit radiation in the form of particles and energy. This generally changes the number of protons and/or neutrons in the nucleus, resulting in a more stable nuclide. One type of a nuclear reaction is radioactive decay, a reaction in which a nucleus spontaneously disintegrates into a slightly lighter nucleus, accompanied by the emission of particles, energy, or both.
    • 7.4: Ionizing Radiation
      The effects of radiation on matter are determined primarily by the energy of the radiation. Nonionizing radiation is relatively low in energy; when it collides with an atom in a molecule or an ion, most or all of its energy can be absorbed without causing a structural or a chemical change. In contrast, ionizing radiation is higher in energy, and some of its energy can be transferred to one or more atoms with which it collides as it passes through matter.
    • 7.5: Nuclear Fission and Nuclear Fusion
      Nuclear energy comes from tiny mass changes in nuclei as radioactive processes occur. In fission, large nuclei break apart and release energy; in fusion, small nuclei merge together and release energy.
    • 7.6: Half-Life and Nuclear Decay Kinetics
      Natural radioactive processes are characterized by a half-life, the time it takes for half of the material to decay radioactively. The amount of material left over after a certain number of half-lives can be easily calculated.
    • 7.7: Radiation Units
      We previously used mass to indicate the amount of radioactive substance present. However, this is only one of several units used to express amounts of radiation. Some units describe the number of radioactive events occurring per unit time, while others express the amount of a person's exposure to radiation.

    • Was this article helpful?