Question

When a radioactive isotope releases an alpha particle, the atomic number of the atom is

Answer 1

The atomic number decreases by 2 and the relative atomic mass decreases by 4, emitting a helium nucleus(having charge of +2) .

Answer 2

Answer: Thus atomic number of the atom decreases by 2 units.

Explanation: Alpha decay : When a larger nuclei decays into smaller nuclei by releasing alpha particle. In this process, the mass number and atomic number is reduced by 4 and 2 units respectively.

General representation of an element is given as:$_Z^A\textrm{X}$

where,

Z represents Atomic number

A represents Mass number

X represents the symbol of an element

General representation of alpha decay :

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