## Question 1.13 [ENDORSED]

H-Atom ($E_{n}=-\frac{hR}{n^{2}}$)

Matthew 1C
Posts: 47
Joined: Fri Sep 29, 2017 7:06 am

### Question 1.13

a) Use the Rydberg formula for atomic hydrogen to calculate the wavelength of radiation generated by the transition from n=4 to n=2. I understand the calculation of the change in energy, but in calculating the wavelength using the equation lambda= ch/E, why do we discard the negative?

Chem_Mod
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### Re: Question 1.13  [ENDORSED]

The negative has to do with if the light is being absorbed or emitted. If it is absorbed, it is positive. Emitted, it is negative. Because this transition is a lowering in energy, this energy is emitted as a photon.