Energy Levels: A hydrogen atom is excited to the n = 9 level. Its decay to the n = 6 level detected in a photographic plate. What is the frequency of the light photographed? (1 eV = 1.60 × 10-19 J, h = 6.626 × 10-34 J ? s)
A. 5.08 × 1013 Hz
B. 5910 Hz
C. 5910 nm
D. 3.28 × 10-9 km
Answer: A
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