MCQ
Radioactive substances do not emit
  • A
    Electron
  • B
    Helium nucleus
  • C
    Positron
  • Proton

Answer

Correct option: D.
Proton
d
Radioactive decay is the process by which a nucleus of an unstable atom loses energy by emitting radiation.

Alpha decay occurs when the nucleus ejects an alpha particle (helium nucleus). This is the most common process of emitting nucleons, but in rarer types of decays, nuclei can eject protons, or in the case of cluster decay specific nuclei of other elements.

Beta decay occurs when the nucleus emits an electron or positron and a neutrino, in a process that changes a proton to a neutron or the other way about. In general, protons are not emitted by a radioactive substance.

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