Question

Isobars are :

• A. the atoms of same element having the same atomic number but different mass numbers
• B. the atoms of same element having different atomic numbers but same mass number
• C. atoms of different elements with same atomic number which have different mass numbers
• D. atoms of different elements with different atomic numbers which have same mass number

Answer 1

The correct option is D atoms of different elements with different atomic numbers which have same mass number

Isobars are atoms or nuclides of separate chemical elements having the same number of nucleons (protons+ neutrons).

The name was given by Alfred Walter Stewart in 1918. It is originally taken from the combination of Greek words- isos means equal and bar means weight.

Atoms of chemical elements having same atomic mass but a different atomic number are called Isobars. The sum of the number of protons and neutrons together form the atomic mass. Therefore, we can also say the number of nucleons present in the nucleus is equal to the atomic mass of an atom. It will have the same number of nucleons.