The following table gives the wavelengths of light given off when electrons change between the energy levels in hydrogen as described in the first row:
Transition of n
3→2
4→2
5→2
6→2
7→2
8→2
9→2
∞→2
Wavelength (nm)
656.3
486.1
434.1
410.2
397.0
388.9
383.5
364.6
Colour
Red
Blue-green
Violet
Violet
(Ultraviolet)
(Ultraviolet)
(Ultraviolet)
(Ultraviolet)
1. Calculate the potential energy of an electron at level n=2.
2. Calculate the difference in potential energy between levels n=2 and n=3.
This time, let's derive a general formula:
3. What is the potential energy of an electron at level n=3?
4. If an electron were to jump from n=7 to n=5, what would the wavelength of the photon given off be?
5. Prove that the wavelength of light emitted from the transition n=4 to n=2 is 486.1 nm (HINT: and )