Multiple Choice
A star shows strong hydrogen Balmer lines but weak lines of neutral sodium.Which is a likely explanation for this phenomenon?
A) There is no sodium in this particular star.
B) The sodium atoms have all been completely ionized.
C) The neutral sodium is receiving so much energy that the energy levels responsible for its usual spectrum are being depopulated.
D) The neutral sodium is not receiving enough energy to excite its electrons to higher energy levels.
Correct Answer:

Verified
Correct Answer:
Verified
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