Alpha particles, which are helium nuclei
that have 2 protons and 2 neutrons.
Beta particles, which are either high-energy
electrons or positrons.
Gamma rays, electromagnetic waves in the
form of photons that have no mass.
Radioactive decay is spontaneous, meaning that it happens all the time and cannot be controlled or stopped. The emission of particles results in a change in the number of protons and neutrons in the nuclide. This may cause the nuclide of a certain element to become the nuclide of another element.
As an example, let's say we liken this lemon to the nuclide of an atom.
Lemon.
After many, many years (Assuming that the lemon does not rot), the lemon has undergone radioactive decay and has become a lime.
Lime. Do note that it is smaller than the lemon.
After many, many, many, many more years after that, the lime also undergoes radioactive decay. It now forms a hedgehog.
Yes. A hedgehog.
The nuclide which decays is called the parent nuclide whereas the new nucleus formed is known as the daughter nuclide.
Alpha Decay
When an atom decays by alpha emission, its nucleon number will decrease by 4 while its proton number decreases by 2.
General formula.
Beta Decay
When an atom decays by beta emission, its nucleon number remains the same but its proton number will increase by 1.The nucleon number does not change as the total number of protons and neutrons does not change. This is because an electron is expelled from the nucleus and is emitted as a high energy beta particle.
An example.
Gamma Emission
When an unstable atom decays through the emission of alpha or beta particles, the atom is sometimes left with excess energy. This energy is emitted as high frequency electromagnetic waves known as gamma rays. The emission of gamma rays has no effect on either the proton or nucleon number.
This.
Thus ends this column on radioactive decay.
