November 16, 2024, 06:39:44 PM
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Topic: Quantum Theory: Determining delta E and wavelength of an electron transition  (Read 8611 times)

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Offline potions09

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Hi,
In my chemistry textbook, there is one example of a question where an electron jumps from one energy level to another, and they ask you to calculate the change in energy and the wavelength of the photon. The sample question explains that you use Bohr's equation first to find delta E (Delta E= (-2.18x10^-18) (1/n final^2 - 1/n initial^2), where n is the energy level of the atom.) Afterwards, they use the equation Delta E=hv to find v, in order to find wavelength. But in this case, n initial =4 and n final=1, so the energy level transition is greater than 1. Thus, shouldn't they use the equation Delta E = (Delta n)(hv) instead of just Delta E=hv? Cuz they mentioned the first equation in the textbook as well.
Thanks in advance!
         

Offline Schrödinger

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No you've got it wrong.

ΔE = nhν. Here, n represents the number of photons, not the energy level. Energy of each photon is hv. Hence you multiply by n to get total energy

In Bohr's equation, the n2 term in the denominator refers to the energy level, not the number of photons. The n's don't represent the same thing in these 2 equations.

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Offline potions09

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Ohh, i get it, i'm so dumb. Thank you!

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