Question

The radius of the stationary state which is also called Bohr radius is given by the expression $r_n=n^2{a}_0$ where the value of $a_0$ is:

• A. 52.9 pm
• B. 5.29 pm
• C. 529 pm
• D. 0.529 pm

Answer 1

Answer: (A)

52.9 pm

The radii of the $n^{th}$ stationary states of Hydrogen and Hydrogen like atom is given by:

$r_n=a_0\frac{n^2}{Z}$

where $a_0=52.9pm,n=n^{th}$Bohr orbit, $Z$=atomic number .

The radius of the first stationary state of Hydrogen atom $(n=1)$, is called as Bohr radius that has a value of $52.9pm$. As n increases the value of r will increase. In other words, the electron will be present away from the nucleus.