When an electron jumps from n=4 to n=2 orbit in a hydrogen atom, we get,

Options

A. Second line of Balmer series
B. Second line of Paschen series
C. An absorption line of Balmer series
D. Second line of Lyman series

Explanation

To solve the question regarding the transition of an electron from the n=4 to n=2 orbit in a hydrogen atom, we can follow these steps:

### Step 1: Understand the Energy Levels
In a hydrogen atom, electrons occupy discrete energy levels, denoted by quantum numbers n=1, n=2, n=3, n=4, etc. The energy of an electron in a particular orbit is given by the formula:
\[ E_n = -\frac{13.6 \, \text{eV}}{n^2} \]
where \( n \) is the principal quantum number.

### Step 2: Identify the Transition
The transition in question is from n=4 to n=2. This means the electron is moving from a higher energy level (n=4) to a lower energy level (n=2). When an electron transitions to a lower energy level, it emits energy in the form of a photon.

### Step 3: Determine the Series
The transition from n=4 to n=2 falls within the Balmer series, which involves transitions to the n=2 level. The Balmer series is characterized by visible light emissions.

### Step 4: Identify the Specific Line
In the Balmer series, the lines are numbered based on the initial energy level (n=3 to n=2 is the first line, n=4 to n=2 is the second line). Therefore, the transition from n=4 to n=2 corresponds to the second line of the Balmer series.

### Step 5: Conclusion
Thus, when an electron jumps from n=4 to n=2 in a hydrogen atom, we get the second line of the Balmer series.

### Final Answer
The answer is: **Second line of the Balmer series.**

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