CBSE NOTES CLASS 12 PHYSICS
CHAPTER 13 NUCLEUS
The atoms of an element having same atomic number but different mass numbers are called isotopes.
e.g., 11H, 21H, 31H are isotopes of hydrogen.
The atoms of different elements having same mass numbers but different atomic numbers are called isobars.
The atoms of different elements having different atomic numbers and different mass numbers but having same number of neutrons are called isotones.
Atoms having the same mass number and the same atomic number but different radioactive properties are called isomers,