Question

Radioactive elements emit $\alpha ,\beta \text{and}\gamma$rays and are characterised by their half-lives. The radioactive isotope of hydrogen is

• A. Protium
• B. Tritium
• C. Deuterium
• D. Hydronium

Answer 1

The correct option is B Tritium

Tritium has one electron, one proton and two neutrons in it. Since the number of neutrons is double than the number of protons in tritum, it makes the nucleus unstable.

Therefore, tritium is the radioactive isotope of hydrogen and it will undergo radioactive decay.

Protium is an isotope of hydrogen with one electron, one proton and zero neutron. It is not a radioactive isotope.
Deuterium is an isotope of hydrogen with one electron, one proton and one neutron ant it is alo not a radioactive isotope.

Hydronium is a common name for $H_3{O}^{+}$ ion and it is not an istope of hydrogen.

HEnce, option (C) is correct.