Question

Of the following transitions in the Hydrogen atom, the one which gives an emission line of the highest frequency is

• A. $n=1$ and $n=3$
• B. $n=2$ to $n=1$
• C. $n=3$ to $n=10$
• D. $n=10$ to $n=3$

Answer 1

The correct option is B $n=2$ to $n=1$

$E_1=-13.6-(-3.4)=-10.2eV$
$E_2=-3.4-(-13.6)=+10.2eV$
$E_3=-0.136-(-1.51)=+1.374eV$
$E_4=-1.51-(-0.136)=-1.374eV$
When an electron makes transition from higher energy level having energy $E_2\left(n_2\right)$ to lower energy having energy $E_1\left(n_1\right)$, then a photon of frequency $\nu$ is emitted.

Frequency of photon emitted $\nu =\frac{E}{h}$
Here, for emission line $E_1$ is maximum hence, it will have the highest frequency emission line.

Correct answer is option B.