OpenStax Chemistry: Atoms First 2e
3.1: Electromagnetic Energy
Chemistry: Atoms First 2e
3: Electronic Structure and Periodic Properties of Elements
3.1: Electromagnetic Energy
1. The light produced by a red neon sign is due to the emission of light by excited neon atoms.
Qualitatively describe the spectrum produced by passing light from a neon lamp through a prism.
Solution
The spectrum consists of colored lines, at least one of which (probably the brightest) is red.
2. An FM radio station found at 103.1 on the FM dial broadcasts at a frequency of 1.031 108 s–
1
(103.1 MHz). What is the wavelength of these radio waves in meters?
Solution
3. FM–95, an FM radio station, broadcasts at a frequency of 9.51 107 s–1 (95.1 MHz). What is
the wavelength of these radio waves in meters?
Solution
4. A bright violet line occurs at 435.8 nm in the emission spectrum of mercury vapor. What
amount of energy, in joules, must be released by an electron in a mercury atom to produce a
photon of this light?
Solution
5. Light with a wavelength of 614.5 nm looks orange. What is the energy, in joules, per photon
of this orange light? What is the energy in eV (1 eV = 1.602 10−19 J)?
Solution
c = λν
6. Heated lithium atoms emit photons of light with an energy of 2.961 10–19 J. Calculate the
frequency and wavelength of one of these photons. What is the total energy in 1 mole of these
photons? What is the color of the emitted light?
Solution
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3.1: Electromagnetic Energy
Chemistry: Atoms First 2e
3: Electronic Structure and Periodic Properties of Elements
3.1: Electromagnetic Energy
1. The light produced by a red neon sign is due to the emission of light by excited neon atoms.
Qualitatively describe the spectrum produced by passing light from a neon lamp through a prism.
Solution
The spectrum consists of colored lines, at least one of which (probably the brightest) is red.
2. An FM radio station found at 103.1 on the FM dial broadcasts at a frequency of 1.031 108 s–
1
(103.1 MHz). What is the wavelength of these radio waves in meters?
Solution
3. FM–95, an FM radio station, broadcasts at a frequency of 9.51 107 s–1 (95.1 MHz). What is
the wavelength of these radio waves in meters?
Solution
4. A bright violet line occurs at 435.8 nm in the emission spectrum of mercury vapor. What
amount of energy, in joules, must be released by an electron in a mercury atom to produce a
photon of this light?
Solution
5. Light with a wavelength of 614.5 nm looks orange. What is the energy, in joules, per photon
of this orange light? What is the energy in eV (1 eV = 1.602 10−19 J)?
Solution
c = λν
6. Heated lithium atoms emit photons of light with an energy of 2.961 10–19 J. Calculate the
frequency and wavelength of one of these photons. What is the total energy in 1 mole of these
photons? What is the color of the emitted light?
Solution
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