Chapter 10 – Review
10.1 Electromagnetic Radiation & 10.2 The Bohr Atom
- 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.
Check Answer: [1] - The laser on a Blu-ray player has a wavelength of 405 nm. In what region of the electromagnetic spectrum is this radiation? What is its frequency?
Check Answer: [2] - CKUN-FM is a First Nations/community radio station broadcasting at 101.3 FM dial in Christian Island, Ontario, Canada broadcasts at a frequency of 1.013 × 108 s−1 (101.3 MHz) (Wikipedia, 2022). What is the wavelength of these radio waves in meters?
Check Answer: [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?
Check Answer: [4] - A bright violet line occurs at 435.8 nm in the emission spectrum of mercury vapour. What amount of energy, in joules, must be released by an electron in a mercury atom to produce a photon of this light?
Check Answer: [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)?
Check Answer: [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 colour of the emitted light?
Check Answer: [7] - A photon of light produced by a surgical laser has an energy of 3.027 × 10−19 J. Calculate the frequency and wavelength of the photon. What is the total energy in 1 mole of photons? What is the colour of the emitted light?
Check Answer: [8] - When rubidium ions are heated to a high temperature, two lines are observed in its line spectrum at wavelengths (a) 7.9 × 10−7 m and (b) 4.2 × 10−7 m. What are the frequencies of the two lines? What colour do we see when we heat a rubidium compound?
Check Answer: [9] - The emission spectrum of cesium contains two lines whose frequencies are (a) 3.45 × 1014 Hz and (b) 6.53 × 1014 Hz. What are the wavelengths and energies per photon of the two lines? What colour are the lines?
Check Answer: [10] - One of the radiographic devices used in a dentist’s office emits an X-ray of wavelength 2.090 × 10−11 m. What is the energy, in joules, and frequency of this X-ray? Check Answer: [11]
- The eyes of certain reptiles pass a single visual signal to the brain when the visual receptors are struck by photons of a wavelength of 850 nm. If a total energy of 3.15 × 10−14 J is required to trip the signal, what is the minimum number of photons that must strike the receptor?
Check Answer: [12] - RGB colour television and computer displays use cathode ray tubes that produce colours by mixing red, green, and blue light. If we look at the screen with a magnifying glass, we can see individual dots turn on and off as the