00:01
In this problem, we're going to talk about atomic transitions.
00:03
So let's say that we have a hydrogen atom whose energy levels, en, are equal to minus 13 .6 electron volts divided by n squared.
00:18
And let's say that the atom transitions from an initial state to a final state.
00:26
If an f is greater than an i, then the atom, gains energy and for that reason it absorbs a photon.
00:52
Now, if an f is smaller than an i, then the electron loses energy, and for that reason, it emits a photon.
01:10
And also, we need to remember that the energy of the photon is just equal to the difference of energy between the two energy levels and the energy of the photon is h .c.
01:24
Over lambda.
01:26
And we have these four transitions here.
01:30
And i is the initial energy level, and f is the final one.
01:34
And in question a, we have to find what is the longest wavelength of the photon emitted or absorbed by these transitions.
01:44
Well, since the energy of the photon is equal to h .c.
01:47
Over lambda, the longest wavelength corresponds to the smallest possible energy.
01:52
So let's calculate the energy in the transition between the two states in each case.
01:59
Just remember that the energy in its transition is equal to the energy of the final energy level minus the energy of the initial energy level.
02:14
If the energy is negative, then the item emitted a photon.
02:21
If it's positive, then the atom absorbed a fold.
02:27
And this is equal to 13 .6 electron volts times 1 over nf squared minus 1 over n i squared.
02:38
In case 1, the transition is between the state 6 and the state 2.
02:45
So delta e is equal to 13 .6 electron volts.
02:57
And actually, i'm sorry, there is one mistake here...