Question

Which of the following spectral series of hydrogen atom is lying in visible range of electromagnetic wave ?

• A. Paschen series
• B. Balmer series
• C. Lyman series
• D. pfund series

Answer 1

Answer: (B)

When an atom comes down from some higher energy level to the second energy level $(n_1=2$ and $n_2=3,4,5,\dots )$, then the lines of the spectrum are obtained in the visible part.
These lines were seen and studied for the first time by Balmer in 1885. The longest wavelength of this series (for $n=3$ ) is $6563\mathring{A}$ and the shortest wavelength (for $n=\infty )$ is $3646\mathring{A}$. So, Balmer series is present in visible range of electromagnetic wave.