Hydrogen has three isotopes 1H, 2H, and 3H. What is the difference between these three isotopes?

Isotopes of the same element have the same number of protons but different numbers of neutrons. Each hydrogen isotope has 1 proton; ¹H has 0 neutrons, ²H has 1, and ³H has 2. Therefore, the number of neutrons ranges from 0 to 2, as choice C states.

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