00:01
So the energy of the photon in the first transition, e1, which is the 2p3 halves to the 2s1 half, is given by hc over lambda 1, where lambda 1 is the wavelength of the photon in that transition, which we're told is 67 times 10 to the minus 6 meters.
00:22
So hc over lambda 1.
00:27
So this gives us a value of energy of 1 .848 times 10 to the 0 .10 .1 .2 .1.
00:37
To the minus 2 electron volts.
00:52
E2, the energy of the photon in the second transition, for the 2p 1 1ā2 to the 2s 1ā2 is hc over lambda 2, where lambda 2 is equal to 67 .09761 times 10 to the minus 6 meters.
01:24
So actually we're going to need to write more significant digits here.
01:28
Sorry about that.
01:29
Because these are so close, we need to include all the significant digits that we have.
01:32
So this is 1 .4 .8 .0 .8 .5 .0 .0.
01:34
So this is 1 .4 .8 .4.
01:34
848 0555 times 10 to the minus 2 meters or 10 to the minus 2 electron volts.
01:57
So for the second one, we get 1 .848...