1. Protium (Hydrogen-1, ₁¹H)
* Symbol: ¹H
* Atomic Number (Z): 1 (This indicates one proton)
* Mass Number (A): 1 (This indicates one proton and no neutrons)
2. Deuterium (Hydrogen-2, ₁²H)
* Symbol: ²H or D
* Atomic Number (Z): 1
* Mass Number (A): 2 (This indicates one proton and one neutron)
3. Tritium (Hydrogen-3, ₁³H)
* Symbol: ³H or T
* Atomic Number (Z): 1
* Mass Number (A): 3 (This indicates one proton and two neutrons)
Key Points:
* Atomic Number (Z): Always remains 1 for all isotopes of hydrogen, since the defining characteristic of hydrogen is having one proton.
* Mass Number (A): Changes based on the number of neutrons present.
* Symbols: While ¹H, ²H, and ³H are the standard notations, D and T are commonly used for deuterium and tritium respectively.
