An isotope has the same number of protons and rich other feature

The number of electrons

Explanation:

Isotopes are essentially known as species of exactly same type of element (which implies that the number of protons in isotopes is same) differing only by the number of neutrons in the nucleus. According to this definition, we may think about the composition of an atom and remember the third component that hasn't been discussed: the electrons.

The number of electrons for any atomic species is equal to the number of protons present, so that an atom is neutral. Therefore, the number of electrons for every isotope should be equivalent.

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