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Railways PYQCBT 1 2016

RRB NTPC · Question 78

_______ are atoms/molecules/ions containing the same number of electrons. A. Isotones B. Isotopes C. Isoelectronic D. Valence Isoelectronic

  1. C

  2. A

  3. D

  4. B

Show answer & explanation

Answer: (A) C

Explanation

Atoms, ions or molecules with the same number of electrons are called isoelectronic, for example Na⁺, Ne and F⁻, each with 10 electrons. Isotopes share the same number of protons, and isotones the same number of neutrons.