Ch. 6 - Iowa State University

Ch. 6:
Sec. 6.2-6.4
Supplemental Instruction
Iowa State University
Chem 167
1. The photochemical reaction that initiate the production of smog involves the
decomposition of NO molecules, and the wavelength of light needed to break the
N-O bond is 191 nm.
a. What is the energy per photon needed to break the bond?
b. How many photons are needed to decompose 0.32 mg of NO?
c. How much total energy is needed to decompose 0.32 mg of NO?
2. TRUE or FALSE: In the Bohr model of the atoms, electrons move between allowed
orbits when an atom emits or absorbs light.
3. What is the energy change when an electron drops from the n=3 energy state to the �=1
energy state in a hydrogen atom?
4. What frequency of light would be needed to make an electron in a Hydrogen atom jump
from n=1 to n=3?
5. Consider an atom with three energy levels. A photon with wavelength 333 nm is emitted
when an electron goes from level 3 to level 1, and a photon of wavelength 683 nm is
emitted when an electron moves from level 2 to level 1. What is the wavelength of a
photon moving from level 3 to level 2?
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