Which of the following is the correct plot for the probability density $\psi^{2}(\mathrm{r})$ as a function of distance $'\mathrm{r}'$ of the electron from the nucleus for 2s orbital?

JEE Main · 2022 · 29 Jun 2022 · Shift 2 · Atomic Structure

Which of the following is the correct plot for the probability density

ψ^{2} (r)

as a function of distance

^{'} r^{'}

of the electron from the nucleus for 2s orbital?

Answer: (B)

For a 2s orbital, the number of radial nodes = n - l - 1 = 2 - 0 - 1 = 1. The probability density

ψ^{2}

is always positive (it's a squared quantity). The correct plot shows one radial node (where

ψ^{2} = 0

) and positive values throughout, which corresponds to option (B).

JEE Main · 2022 · 29 Jun 2022 · Shift 2 · Single correct option