1.what happens in the nucleus of an atom when an alpha particle is emitted?
2. what happens in the nucleus of an atom when a beta particle is emitted?

1. The mass number is reduced by 4 units and atomic number is reduced by 2 units

2. Mass number remains same but the atomic number is increased by 1.

Explanation:

Alpha Decay: In this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. The mass number is reduced by 4 units and atomic number is reduced by 2 units.

Beta Decay : It is a type of decay process, in which a proton gets converted to neutron and an electron. This is also known as -decay. In this the mass number remains same but the atomic number is increased by 1.

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