Question

Check the correctness of the following statements about the Bohr Model of hydrogen atom:
$\left(i\right)$ The acceleration of the electron in $n=2$ orbit is more than that in $n=1$ orbit.
$\left(ii\right)$ The angular momentum of the electron in $n=2$ orbit is more than that in $n=1$ orbit.
$\left(iii\right)$ The KE of the electron in $n=2$ orbit is less than that in $n=1$ orbit

• A. All the statements are correct
• B. Only $\left(i\right)$ and $\left(ii\right)$ are correct
• C. Only $\left(ii\right)$ and $\left(iii\right)$ are correct
• D. Only $\left(iii\right)$ and $\left(i\right)$ are correct

Answer 1

The correct option is C Only $\left(ii\right)$ and $\left(iii\right)$ are correct

Angular momentum, $L=mv{r}_n=\frac{nh}{2\pi }\propto n$
Hence, (ii) is correct.
Velocity of $2^{nd}$ orbit is less so kinetic energy is also less.

Hence, (iii) is correct.
The radius of $2^{nd}$ orbit is $4$ times the radius of $1^{st}$ orbit.
Thus, acceleration $\left(v^2/r\right)$ in $n=2$ is less than the $n=1$.
Hence, (i) is incorrect.