Calculating Longest Wavelength of Light to Eject Electrons

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SUMMARY

The discussion focuses on calculating the longest wavelength of light required to eject electrons from a surface, given an energy threshold of 254 kJ/mole. To solve this, one must first convert the energy per mole to energy per electron, using Avogadro's number. The relationship between energy and wavelength is established through the equation E = hc/λ, where E is energy, h is Planck's constant, c is the speed of light, and λ is the wavelength. The user is encouraged to utilize OpenCourseWare (OCW) resources from MIT and Tufts for further understanding of quantum mechanics.

PREREQUISITES
  • Understanding of quantum mechanics principles
  • Familiarity with the concept of energy quantization
  • Knowledge of Avogadro's number
  • Basic proficiency in using the equation E = hc/λ
NEXT STEPS
  • Calculate energy per electron from 254 kJ/mole using Avogadro's number
  • Learn about Planck's constant and its application in quantum mechanics
  • Explore the relationship between frequency and wavelength in electromagnetic radiation
  • Review OpenCourseWare resources on quantum mechanics from MIT and Tufts
USEFUL FOR

Students in chemistry or physics courses, educators teaching quantum mechanics, and anyone interested in the photoelectric effect and its applications.

chemilliterate
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Please Help! (Quantum Mechanics)

I posted this in the Quantum Physics forum as well, but I ran across this one and thought it may help to put it here too. Sorry for the double post.

Hi everyone... I am new to this site. I am currently taking a major-related Chemistry course that is concentrating on quantum mechanics right now. I have been working on a homework question for about an hour now, and I am no closer to figuring it out than when I started. Something tells me that it's probably a pretty easy question, if I just knew where to begin. I need to calculate the longest wavelength (minimum frequency, right?) of light in nm that can be used to eject electrons from a surface, given that it takes 254kJ/mole. Can someone please help me!
 
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Light comes in packets. How much energy that packet has depends on the frequency. You need to find the energy it takes to eject a single electron (remember the size of a mole?) and find the frequency of light that has that amount of energy per packet (or quantum).
 
Thank you, thank you, thank you, thank you, thank you! You are a life saver! I was trying to make things way too difficult! :biggrin:
 
You can get a better understanding of Quantum Mechanics basics through OCW courses. Check out the following ocw courses from MIT and TUFTS.
http://www.opencontentonline.com/search.php?query_text=quantum+mechanics

Cheers
Trilateral
 
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