Question

The wave function $(\Psi)$ of $2 s$ is given by
$\Psi_{2 n }=\frac{1}{2 \sqrt{2 \pi}}\left(\frac{1}{a_0}\right)^{1 / 2}\left(2-\frac{r}{a_0}\right) e^{-\frac{r}{2 a_0}}$
At $r=r_0$, radial node is formed. Thus, $r_0$ in terms of $a_0$

• A. $r_0=\frac{a_0}{2}$
• B. $r_0=2 a_0$
• C. $r_0=4 a_0$
• D. $r_0=a_0$

Answer 1

Answer: (B)

At node $\Psi_{2 s}=0$
$ \therefore 2-\frac{r_0}{a_0}=0 $
$\therefore r_0=2 a_0$