Question

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

Answer 1

Answer: 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.

$_A^Z\textrm{X}\rightarrow _{A-2}^{Z-4}+_2^4\alpha$

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 $\beta ^-$-decay. In this the mass number remains same but the atomic number is increased by 1.

$_A^Z\textrm{X}\rightarrow _{A+1}^Z\textrm{Y}+_{-1}^0e$

Answer 2

1) The nucleus of an atom loses 2 protons and 4 neutrons.
2) The nucleus of an atom gains a proton and it's neutrons remain the same.