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Guilherme Mazui

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What is the Difference Between Alpha and Beta Decay?

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Alpha and beta decay are two types of radioactive decay processes that occur in the nucleus of an atom. The main differences between them are:

  1. Particles involved: In alpha decay, the nucleus loses two protons and two neutrons, in the form of a helium nucleus (α-particle). In beta decay, the nucleus either loses a proton (beta plus decay) or gains a proton (beta minus decay).
  2. Mass change: Alpha decay results in a decrease in the total mass of the nucleus, while beta decay does not change the mass.
  3. Atomic number change: Beta decay changes the atomic number of the atom by one, as the proton stays in the nucleus, while the electron is ejected. In alpha decay, the atomic number does not change, but the mass number decreases by four.
  4. Penetration power: Alpha particles have a lower penetration power compared to beta particles, and they can be stopped by a thick sheet of paper or the outer layer of dead skin on people. Beta particles have a higher penetration power and can cause more damage to tissue.

In summary, alpha decay involves the loss of a helium nucleus (two protons and two neutrons), while beta decay involves the transformation of a neutron into a proton or vice versa. Alpha decay results in a decrease in mass and does not change the atomic number, while beta decay does not change the mass but increases the atomic number by one. Alpha particles have a lower penetration power than beta particles.

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  • What is the Difference Between Alpha and Beta Decay?
  • Comparative Table: Alpha vs Beta Decay

    • Comparative Table: Alpha vs Beta Decay

    Here is a table comparing the differences between alpha and beta decay:

    Property Alpha Decay Beta Decay
    Definition Alpha decay is a common mode of radioactive decay in which a nucleus emits an alpha particle (a helium-4 nucleus). Beta decay is a common mode of radioactive decay in which a neutron is transformed into a proton, accompanied by the emission of an electron.
    Particle Emitted Alpha particle, which consists of two protons and two neutrons. Beta particle, which is an electron.
    Penetrating Power Minimum. Variable, depending on the energy of the beta particle.
    Atomic Number Change Yes, it increases by two, as the emitted alpha particle contains two protons. No, but the atomic number increases by one due to the conversion of a neutron to a proton.
    Mass Number Change No, it remains the same, as the emitted alpha particle has the same mass number as the parent nucleus minus 4. Yes, it decreases by one, as a neutron is converted to a proton, reducing the total mass number.

    In summary, alpha decay involves the emission of a helium nucleus (alpha particle), resulting in a decrease in the atomic number and no change in the mass number. On the other hand, beta decay involves the transformation of a neutron into a proton and the emission of an electron, causing an increase in the atomic number and a decrease in the mass number. Beta particles have variable penetrating power, while alpha particles have minimal penetrating power.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.