The third in Balmer series corresponds to an electronic transition between which Bohr's orbits in hydrogen

Options

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

Explanation

To determine the electronic transition corresponding to the third line in the Balmer series for hydrogen, we can follow these steps:

### Step 1: Understand the Balmer Series
The Balmer series describes the spectral lines resulting from electronic transitions in hydrogen where the electron falls to the second energy level (n=2) from higher energy levels (n=3, n=4, n=5, etc.). The lines in this series are denoted by the principal quantum number of the initial orbit (n) from which the electron transitions to n=2.

### Step 2: Identify the Third Line in the Balmer Series
The lines in the Balmer series are numbered based on the initial energy level (n) from which the electron transitions to n=2:
- The first line (Hα) corresponds to the transition from n=3 to n=2.
- The second line (Hβ) corresponds to the transition from n=4 to n=2.
- The third line (Hγ) corresponds to the transition from n=5 to n=2.

### Step 3: Determine the Transition for the Third Line
From the understanding of the Balmer series, we can conclude that the third line (Hγ) corresponds to the transition of an electron from the fifth energy level (n=5) to the second energy level (n=2).

### Final Answer
The third line in the Balmer series corresponds to the electronic transition from the 5th orbit (n=5) to the 2nd orbit (n=2) in hydrogen.

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