A spontaneous process where an unstable nucleus changes into a more stable nucleus by emitting radiations.
The release of high-energy particles.
The characteristics of the radioactive radiation:
The process by which unstable nuclei emit radioactive rays to be more stable nuclei.
Spontaneous: the decay rate is not controlled, happens by itself, not affected by the chemical composition or physical factors (temperature, pressure, light, electric and magnetic fields)
\(^A _Z X \space \rightarrow ^{A-4} _{Z-2} Y + ^4 _2 \text He\)
where,
\(^{A-4} _{Z-2} Y\) is the new element and,
\(^{4} _2 \text He\) is the alpha particle.
\(^A _Z X \space \rightarrow \space ^A _{Z+1} R+ ^0 _{-1} \beta\)
\(^{A} _{Z+1} R\) is the new element and,
\(^{0} _{-1} \beta\) is the beta particle.
\(^A _Z \text X \rightarrow ^A _Z \text X + T\)
When a radioisotope emits a gamma-ray, it does not change the value of the nucleon number (\(A\)) or the value of the proton number (\(Z\)).
No new element will be created when a nucleus emits a gamma-ray.
The time taken by a radioactive sample to decay by half of its original mass.
The concept of half-life can be described as follows:
The half-life value can be determined from the graph of the activity against time or the graph of the number of atoms, N radioactive against time:
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