when an electron jumps from the fourth orbit to the second orbit, one gets the

Options

A. second line of paschen series
B. second line of balmer serie
C. first line pfund series
D. second line of lyman series

Explanation

To solve the problem of determining what happens when an electron jumps from the fourth orbit to the second orbit, we can follow these steps:

### Step 1: Understand the Energy Levels
In the Bohr model of the atom, electrons occupy specific energy levels or orbits, which are denoted by quantum numbers (n). The energy levels are quantized, meaning that an electron can only exist in these defined states.

### Step 2: Identify the Transition
The question specifies that the electron is transitioning from the fourth orbit (n = 4) to the second orbit (n = 2). This transition can be represented as:
- Initial state (n_initial) = 4
- Final state (n_final) = 2

### Step 3: Determine the Series
Transitions between energy levels result in the emission or absorption of light, which can be categorized into series based on the final energy level:
- If n_final = 1, it corresponds to the Lyman series (ultraviolet region).
- If n_final = 2, it corresponds to the Balmer series (visible region).
- If n_final = 3, it corresponds to the Paschen series (infrared region).

Since the final state in our case is n = 2, this transition falls under the **Balmer series**.

### Step 4: Identify the Specific Line in the Series
In the Balmer series, the lines are numbered based on the initial state:
- The transition from n = 3 to n = 2 is the first line (H-alpha).
- The transition from n = 4 to n = 2 is the second line (H-beta).

Thus, when the electron jumps from the fourth orbit to the second orbit, it corresponds to the second line of the Balmer series.

### Conclusion
When an electron jumps from the fourth orbit to the second orbit, it emits a photon corresponding to the **second line of the Balmer series**.

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