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Question
Neutral hydrogen atoms are best studied from their energy given off asA) red hydrogen alpha emission, at 656.3 nm.
B) 121.3 nm as Lyman alpha emission in the UV.
C) 21-cm waves in the radio region.
D) 0.2 nm as X-rays.
E) Neutral hydrogen gives off no detectable radiation, since it is cold, not hot.
Answer
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