[单选题]
The diagram gives energy levels of a single-electron atom.
How many different wavelengths can be detected in the emission spectrum of the atom?
A. 4
B. 5
C. 9
D. 10
参考答案: C
本题详细解析:
Explanation:
With five energy levels there are 10 possible transitions, but in this case the transitions from n=5 to n=3 and n=3 to n=2 are identical in energy difference. Therefore, there are 9 different transitions with different wavelengths.
