Radioactivity is discovered by French scientist Becquerel in 1896. Substances which emits radiation is known as radioactive substances and this property of substances to emit radiation is called as radioactivity.
example : Uranium exhibit radioactivity.
Rutherford conduct some experiments with radioactive substances and his observations are as follows-
1. Rays which turned toward negative electrode is known as alpha rays, mass of alpha particles is 4 a.m.u. and charge is 2 units of positive charge.
2. Rays which turned toward positive electrode is known as beta rays, mass and charge of beta particle is equal to mass and charge of electron.
3. The rays which do not turned towards any electrode is known as gamma rays, gamma rays are electromagnetic rays and not made from matter particle.
Gamma > Beta > Alpha
Gamma rays have maximum penetrating power while Alpha has lowest.
Tracer technique of radioactive isotopes
As per requirement, small amount of radioactive isotopes is added to its element then many physical and chemical complex reaction are studied.
Various fields of tracer techniques
- In the field of chemical science.
- In the field of medical science.
- In the field of agriculture.
- In the industrial fields.
- And in other scientific fields.
In this technique carbon isotope is used to determine the age of rocks, minerals, fossils, dead animals and dead plants.