Question

Why isotopes having different different atomic masses

Answer 1

Hii

Good evening

Isotopes having different different atomic masses because of different numbers neutrons present in the nucleus . Atomic mass is equal to the total number of protons and neutrons.

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Answer 2

Because isotopes have same number of protons and electrons.

But different number of neutrons.

Mass number : protons plus neutrons

So if their neutrons tend to vary, their mass will also change.