Question:
The difference between the radii of $3^{\text {rd }}$ and $4^{\text {th }}$ orbits of $\mathrm{Li}^{2+}$ is $\Delta \mathrm{R}_{1}$. The difference between the radii of $3^{\text {rd }}$ and $4^{\text {th }}$ orbits of $\mathrm{He}^{+}$is $\Delta \mathrm{R}_{2}$. Ratio $\Delta \mathrm{R}_{1}: \Delta \mathrm{R}_{2}$ is :
Correct Option: , 4
Solution: