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Radioactivity

Radioactivity

Property of a nucleus emitting alpha beta and gamma rays is known as radioactivity and the substance possessing the this property is called a radioactive substance the emission of these particles take place because of the instability of nucleus Alpha particle.

nuclear size-

the radius r of various nuclei can be approximately calculated in cm by using the relation .

        r = r'A^1/3

where r' is a constant which is equal to 1.4 × 10^- 13 cm and A is  the mass number of a given nucleus.

Types of radioactive decay

The types of radioactive decay that occurs usually depends on whether the nucleus is above or below are to the right or to the stability belt.

There are five common types of radioactive decay .

Alpha emission-



Beta emission-





Position emission-



Electron capture-



Gamma emission-

 

 

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