Multiple Choice
The ground state of hydrogen has two closely-spaced energy levels, where oneelectron is spinning up and the other is spinning down. This energy transition corresponds to releasing excess energy as a photon at what wavelength?
A) 21 centimeters
B) 21 millimeters
C) 21 meters
D) 22.2 centimeters
E) 22.2 millimeters
Correct Answer:

Verified
Correct Answer:
Verified
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