Which isotope of hydrogen is radioactive ?

Explanation

To determine which isotope of hydrogen is radioactive, we can follow these steps:

### Step 1: Understand the Isotopes of Hydrogen
Hydrogen has three main isotopes:
1. Protium (¹H) - 1 proton, 0 neutrons
2. Deuterium (²H) - 1 proton, 1 neutron
3. Tritium (³H) - 1 proton, 2 neutrons

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