In the diagram, the energy difference between
states A and B is twice the energy difference
between states B and C. In a transition (quantum
jump) from C to B an electron emits a photon of wavelength 600 nm

Find the wavelength λ2 emitted when the
photon jumps from B to A.
Answer in units of nm.

Find the wavelength λ3 emitted when the
photon jumps from C to A.
Answer in units of nm.

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Wavelength lambda = hc/E, so lambda is inversely proportional to E.
A. E(B=>A) = 2E(C=>B) so lambda(B=>A) = lambda(C=>B)/2 = 300 nm
B. E(C=>A) = 3E(C=>B) so lambda(C=>A) = lambda(C=>B)/3 = 200 nm

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