The color of dyes results from the preferential absorption of certain wavelengths of light. Certain dye molecules consist of symmetric pairs of rings joined at the center by a chain of carbon atoms, as shown in (Figure 1). Electrons of the bonds along the chain of carbon atoms are shared among the atoms in the chain, but are repelled by the nitrogen- containing rings at the end of the chain. These electrons are thus free to move along the chain but not beyond its ends. They look very much like a particle in a one-dimensional box. For the molecule shown, the effective length of the "box" is 0.85 nm. Part A Assuming that the electrons start in the lowest energy state, what is the longest wavelength this molecule will absorb? Express your answer with the appropriate units. HA ? Value Units Submit Request Answer

The color of dyes results from the preferential absorption of certain wavelengths of light. Certain dye molecules consist of symmetric pairs of rings joined at the center by a chain of carbon atoms, as shown in (Figure 1). Electrons of the bonds along the chain of carbon atoms are shared among the atoms in the chain, but are repelled by the nitrogen- containing rings at the end of the chain. These electrons are thus free to move along the chain but not beyond its ends. They look very much like a particle in a one-dimensional box. For the molecule shown, the effective length of the "box" is 0.85 nm. Part A Assuming that the electrons start in the lowest energy state, what is the longest wavelength this molecule will absorb? Express your answer with the appropriate units. HA ? Value Units Submit Request Answer

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter3: Atomic Shells And Classical Models Of Chemical Bonding

Section: Chapter Questions

Problem 87AP: At large interatomic separations, an alkali halide molecule MX has a lower energy as two neutral...

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