Question

definition of isotopes and the format to write mass no. and atomic no. with an element

Answer 1

Definition of isotope .

Isotopes are atoms of the same element having the same atomic number but different mass number.

The number of protons are same .

The number of electrons are same .

The number of neutrons are different .

Examples :

Hydrogen isotopes .

$^1_1H$

Mass number = 1

$^2_1H$

Mass number = 2

$^3_1H$

Mass number = 3

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