Question: Isotope(s) of hydrogen which emits low energy $\beta^{-}$ particles with $t_{1 / 2}$ value $>12$ years is/are
Protium
Tritium
Deuterium
Deuterium and Tritium
Correct Option: , 2
Solution:
${ }_{1}^{1} \mathrm{H}$ and ${ }_{1}^{2} \mathrm{H}$ are stable while ${ }_{1}^{3} \mathrm{H}$ is radioactive.
