Difference between the radii of 2nd and 3rd orbits of He+ is Ξ”R₁. The difference between the radii of 3rd and 4th orbits of Li+2 is Ξ”Rβ‚‚. Find Ξ”R₁ / Ξ”Rβ‚‚ | AITS & Test Series β€” Chem-Mantra | Chem-Mantra