Atomic Structure | JEE Main 2025 Solution

JEE MAIN 2025

22-01-2025 SHIFT-1

Question

Radius of the first excited state of Helium ion is given as: ${{\rm{a}}_0} \to$ radius of first stationary state of hydrogen atom.

Select the correct option:

${\rm{r}} = 2{{\rm{a}}_0}$

${\rm{r}} = 4{{\rm{a}}_0}$

${\rm{r}} = \frac{{{{\rm{a}}_0}}}{4}$

$r = \frac{{{a_0}}}{2}$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution

${\rm{r}} = {{\rm{a}}_0}\frac{{{{\rm{n}}^2}}}{{\rm{Z}}} = {{\rm{a}}_0} \cdot \frac{{{{(2)}^2}}}{2} = 2{{\rm{a}}_0}$

Question Tags

JEE Main

Chemistry

Medium

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