Question

Imagine removing one electron from ${}_{2}H{e}^4$ and ${}_{2}H{e}^3$. Their energy levels, as worked out on the basis of Bohr model will be very close. Explain why.

Answer 1

If we remove one electron from the isotopes of ${}_{2}H{e}^4$ and ${}_{2}H{e}^3$, both atoms will have $1$ electron as in H - atom and the nucleus is much (four times) heavier than $H-$ atom, so stability can remain and these atoms are very close to the H atom so the energy levels are as of hydrogen and these atoms will be very close.