Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    1
    ReputationRep:
    Figure 1 shows part of an energy level diagram for a hydrogen atom.

    n=4 ------ -0.85eV
    n=3 ------ -1.50eV
    n=2 ------ -3.40eV
    n=1 ------ -13.60eV

    When an electron of energy 12.1eV collides with the atom, photons of three different energies are emitted.

    [b]Calculate the wavelength of the photon with the smallest energy. Give your answer to an appropriate number of significant figures.

    I get how to do most of this question but how do I know which is the photon with the smallest energy? I found it to be 0.65ev why is it 1.9ev?

    Offline

    9
    ReputationRep:
    I think that you have to assume that the electron bound to the hydrogen atom is in the ground state before the collision. Does that make it clearer?
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Brussels sprouts
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Quick reply
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.