Answer:
Explanation:
(a) Electron Emission (Beta- decay):
When an unstable nucleus decays by the emission of Beta- particle, its charge number ‘Z’ increases by 1 but, its mass number ‘A’ remains unchanged. The transformation is represented by the equation:
[tex]_zX^A\ -------->\ _{Z+1}Y^A\ +\ _{-1}e^0[/tex]
It is called ‘Negative Beta Decay’. It is more common than alpha decay.
Example:
[tex]_6C^{14}\ -------->\ _{7}N^{14}\ +\ _{-1}e^0[/tex]
Note:
There are no electrons in a nucleus so, with the emission of a particle, one of the neutrons is converted to a proton and an electron.
[tex]_0n^1\ --------->\ _1P^1\ +\ _{-1}e^0[/tex]
(b) Positron Emission (Beta+ decay):
When an unstable nucleus decays by the emission of the positron, its charge number ‘Z’ decreases by 1 but, its mass number ‘A’ remains unchanged. The transformation is represented by the equation:
[tex]_zX^A\ -------->\ _{Z-1}Y^A\ +\ _{+1}e^0[/tex]
Examples:
[tex]_{15}P^{30}\ -------->\ _{14}Si^{30}\ +\ _{+1}e^0[/tex]
Note:
Inside the nucleus, only a proton can be transformed into a neutron with the emission of a positron (anti-particle of electron)
[tex]_1P^1\ -------->\ _0n^1\ +\ _{+1}e^0[/tex]
