The third line of the Balmer series, in the emission spectrum of the hydrogen atom, is due to the transition from the

Options

A. fourth Bohr orbit to the first Bohr orbit
B. fifth Bohr orbit to the second Bohr orbit
C. sixth Bohr orbit to the third Bohr orbit
D. seventh Bohr orbit to the third Bohr orbit.

Explanation

To solve the question regarding the third line of the Balmer series in the emission spectrum of the hydrogen atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Balmer Series**: The Balmer series corresponds to the transitions of electrons in a hydrogen atom that end at the n=2 energy level. The transitions can occur from higher energy levels (n=3, n=4, n=5, etc.) down to n=2.

2. **Identify the Lines in the Balmer Series**:
- The first line of the Balmer series occurs when an electron transitions from n=3 to n=2.
- The second line occurs when an electron transitions from n=4 to n=2.
- The third line occurs when an electron transitions from n=5 to n=2.

3. **Determine the Transition for the Third Line**: Since we are looking for the third line, we identify that it corresponds to the transition from n=5 to n=2.

4. **Conclusion**: Therefore, the third line of the Balmer series is due to the transition from the fifth energy level (n=5) to the second energy level (n=2).

### Final Answer:
The third line of the Balmer series in the emission spectrum of the hydrogen atom is due to the transition from n=5 to n=2.

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