In Bohr series of lines of hydrogen spectrum, third line from the red end corresponds to which one of the following inner orbit jumps of electron for Bohr orbit in atom in hydrogen :

Options

A. `4 rarr 1`
B. `2 rarr 5`
C. `3 rarr 2`
D. `5 rarr 2`

Explanation

To determine which inner orbit jumps of electrons correspond to the third line from the red end in the Bohr series of lines of the hydrogen spectrum, we can follow these steps:

### Step 1: Understand the Bohr Series
The Bohr series of lines in the hydrogen spectrum is divided into different series based on the final energy level of the electron. The most commonly referred series are the Lyman series (n=1), Balmer series (n=2), and Paschen series (n=3).

### Step 2: Identify the Series
The lines in the hydrogen spectrum are categorized as follows:
- **Lyman Series**: Transitions to n=1 (ultraviolet region)
- **Balmer Series**: Transitions to n=2 (visible region)
- **Paschen Series**: Transitions to n=3 (infrared region)

Since we are looking for the third line from the red end, we focus on the Balmer series, which corresponds to transitions ending at n=2.

### Step 3: Determine the Lines in the Balmer Series
The lines in the Balmer series correspond to the following transitions:
1. **First line (H-alpha)**: n=3 to n=2
2. **Second line (H-beta)**: n=4 to n=2
3. **Third line (H-gamma)**: n=5 to n=2

### Step 4: Identify the Third Line
The third line from the red end in the Balmer series is the H-gamma line, which corresponds to the transition of an electron from n=5 to n=2.

### Conclusion
Thus, the third line from the red end in the Bohr series of lines of the hydrogen spectrum corresponds to the inner orbit jump of an electron from n=5 to n=2.

### Final Answer
The third line from the red end corresponds to the jump from n=5 to n=2.

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