Atoms And Nuclei

${ }_1^3 \mathrm{H}$ and ${ }_2^3 \mathrm{He}$

${ }_{80}^{198} \mathrm{Hg}$ and ${ }_{79}^{197} \mathrm{Au}$

${ }_1^2 \mathrm{H}$ and ${ }_1^3 \mathrm{H}$

${ }_{92}^{236} \mathrm{U}$ and ${ }_{92}^{238} \mathrm{U}$