Question

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

A. 5 → 2

B. 4 → 1

C. 2 → 5

D. 3 → 2

Answer 1

The third line from the red end in the Bohr series of the hydrogen spectrum corresponds to the electron transition from the 5th orbit to the 2nd orbit (Option A: 5 → 2).

Step-by-step explanation:

The third line from the red end in the Bohr series of lines of the hydrogen spectrum corresponds to the transition of an electron from a higher-energy orbit to a lower-energy orbit within an atom of hydrogen. According to Bohr's model, the Balmer series of the hydrogen emission spectrum includes lines that correspond to transitions from orbits where n > 2 (with n being the principal quantum number) to the second orbit (n = 2).

Consequently, the third line from the red end represents the transition from the fifth orbit to the second orbit, which is the Option A: 5 → 2 transition. This transition results in the emission of a photon and is observed at a wavelength of 434 nm, which appears as a blue line in the spectrum.