4.2.14

Radioactive Decay

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Radioactive Decay

During alpha, beta, and gamma radioactive decay, an unstable nucleus becomes more stable.

Alpha decay

Alpha decay

  • In alpha decay, a nucleus loses an alpha particle.
    • An alpha particle is made from 2 protons and 2 neutrons.
  • Because 2 protons have been lost, we now have a new element.
Alpha decay equation

Alpha decay equation

  • Polonium undergoes alpha decay in the equation:
    • 21884Po21482Pb+42α{{{218}\atop{84} }\text{Po}} \rightarrow {{{214}\atop{82} }\text{Pb}} + {{{4}\atop{2} }{\alpha}}
Beta decay

Beta decay

  • In beta decay, a neutron in the nucleus decays to form a proton and electron.
  • This electron is then ejected out of the nucleus.
Beta decay equations

Beta decay equations

  • Carbon undergoes beta decay in the equation:
    • 146C147N+01β{{{14}\atop{6} }\text{C}} \rightarrow {{{14}\atop{7} }\text{N}} + {{{0}\atop{-1} }{\beta}}
Gamma decay

Gamma decay

  • In gamma decay, the composition of the nucleus is unchanged.
  • The nucleus is said to be “relaxing” from one state into another state with lower energy.
Gamma decay equations

Gamma decay equations

  • Iodine undergoes gamma radiation in the equation:
    • 12553I12553I+00γ{{{125}\atop{53} }\text{I}} \rightarrow {{{125}\atop{53} }\text{I}} + {{{0}\atop{0} }{\gamma}}
Jump to other topics
1

Energy

2

Electricity

3

Particle Model of Matter

4

Atoms & Radiation

5

Forces

5.1

Basics of Motion

5.2

Forces

5.3

Effects of Forces

5.4

Pressure

6

Waves

6.1

Wave Basics

6.2

Waves at a Boundary

6.3

Sound Waves

6.4

Electromagnetic Waves

6.5

Lenses

6.6

Heat & Radiation

7

Magnetism

8

Astrophysics

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