Skip to main content
Ch.6 - Electronic Structure of Atoms
Chapter 6, Problem 91a

The series of emission lines of the hydrogen atom for which nf = 3 is called the Paschen series. (a) Determine the region of the electromagnetic spectrum in which the lines of the Paschen series are observed.

Verified step by step guidance
1
Identify the initial and final energy levels for the Paschen series. The final energy level \( n_f \) is 3, and the initial energy level \( n_i \) is greater than 3.
Use the Rydberg formula for hydrogen to calculate the wavelength of the emitted light: \( \frac{1}{\lambda} = R_H \left( \frac{1}{n_f^2} - \frac{1}{n_i^2} \right) \), where \( R_H \) is the Rydberg constant.
Calculate the wavelengths for transitions from higher energy levels (e.g., \( n_i = 4, 5, 6, \ldots \)) to \( n_f = 3 \).
Determine the range of wavelengths obtained from these calculations.
Identify the region of the electromagnetic spectrum corresponding to these wavelengths, which is the infrared region.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
54s
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Electromagnetic Spectrum

The electromagnetic spectrum encompasses all types of electromagnetic radiation, arranged by wavelength or frequency. It includes gamma rays, X-rays, ultraviolet light, visible light, infrared radiation, microwaves, and radio waves. Each type of radiation has distinct properties and applications, with the visible spectrum being just a small part of the entire range.
Recommended video:
Guided course
02:53
Electromagnetic Spectrum

Hydrogen Emission Spectrum

The hydrogen emission spectrum is the spectrum of light emitted by hydrogen atoms when they transition from higher energy levels to lower ones. Each transition corresponds to a specific wavelength of light, resulting in distinct emission lines. The Paschen series specifically refers to transitions where electrons fall to the n=3 energy level, producing infrared radiation.
Recommended video:
Guided course
01:51
Emission Spectra

Paschen Series

The Paschen series is a set of spectral lines in the hydrogen emission spectrum that occurs when electrons transition to the third energy level (n=3) from higher levels (n=4, 5, 6, etc.). These transitions emit photons in the infrared region of the electromagnetic spectrum, which is not visible to the human eye but can be detected with appropriate instruments.
Recommended video:
Guided course
02:02
Activity Series Chart
Related Practice