Oxford Area High School
Oxford Area High School
College Prep Chemistry
Mr. Urig
Ws #2 Calculating Energy & Wavelength
What is the relationship between wavelength and frequency?
1. The colors of the visible spectrum, and the wavelengths corresponding to the colors, are given in Figure 7.3
A) What colors of the light involves less energy than green light?
B) Which color of light has photons of greater energy, yellow or blue?
C) Which color of light has the greater frequency, blue or green?
2. A) Which type of radiation involves less energy, x-rays or microwaves?
B) Which radiation has the highest frequency, radar or red light?
C) Which radiation has the longer wavelength, ultraviolet or infrared light?
3. An FM radio station has a frequency of 88.9 Hz (1 MHz = 106 Hz, or cycles per second). What is the wavelength of this radiation in meters?
4. The most prominent line in the spectrum of magnesium is 285.2 nm. Others are found at 383.8 and 518.4 nm. In what region of the electromagnetic spectrum are these lines found? Which is the most energetic line? What is the energy of 1 mol of photons of the most energetic line? How much more energetic is a photon of this light compared with a photon associated with the least energetic line?
5. The most prominent line in the spectrum of mercury is found at 253.652 nm. Other lines are found at 365.015 nm, 404.656 nm, 435.833 nm, and 1013.975.
A) Which of these lines represents the most energetic light?
B) What is the frequency of the most prominent line? What is the energy of one
photon with this wavelength?
6. The most prominent line in the spectrum of neon is found at 865.438 nm. Other lines are found at 837.761 nm, 878.062 nm, 878.375 nm, and 1885.387 nm.
A) Which of these lines represents the most energetic light?
B) What is the frequency of the most prominent line? What is the energy of one
photon with this wavelength?
C) Are any of t he lines mentioned here found in the spectrum of neon shown in
Figure 7.9? What color or colors are these lines?
7. Place the following types of radiation in order of increasing energy per photon:
A) yellow light from a sodium lamp.
B) x-rays from an instrument in a dentist’s office
C) microwaves in a microwave oven
D) your favorite FM music station at 91.7 Hz.
8. Place the following types of radiation in order of increasing energy per photon:
A) radar signals
B) radiation within a microwave oven
C) y rays from a nuclear reaction
D) red light from a neon sign
E) ultraviolet radiation from a sun lamp
9. To cause a cesium atom on a metal surface to lose an electron, an energy of 2.0 x 102 kJ/mol is required. Calculate the longest possible wavelength of light that can ionize a cesium atom. What is the region of the electromagnetic spectrum in which this radiation is found?
10. The most prominent line in the line spectrum of aluminum is found at 396.15 nm. What is the frequency of this line? What is the energy of one photon with this wavelength? Of 1.00 mol of these photons?