1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Electron Energy

  1. Feb 18, 2008 #1
    1. The problem statement, all variables and given/known data
    "Mono-energetic electrons are diffracted by a lattice. Their wavelength is shown to be L=0.35nm. What are the energies of the electrons?"


    2. Relevant equations

    E=hf

    c=hL

    3. The attempt at a solution


    c/L gives 8.566exp17

    h=6.626exp-34

    I plug them in and get: 5.66exp-19 J

    The answer is 1184.4 kJ mol -1.

    So I divide my answer by 1000, and multiply it by Avogadros number. But my answer is nowhere near the actual answer. Where am I going wrong?
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted