Question

Isotopes (such as hydrogen-1, hydrogen-2, and hydrogen-3) are atoms of the same

Answer 1

Answer:

a. The number of neutrons in the nucleus

Explanation:

Having more protons or electrons would change the charge of the atom making it an ion. Neutrons have no charge so the overall charge of the atom is not affected; neutrons also have a relative mass of 1 which is why there are different isotopes.

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