氢原子的能级如图所示，一群氢原子处于n=3的能级，向较低能级跃迁过程中，辐射的光子
A．频率最多有3种
B．频率最多有2种
C．能量最大为12.09eV
D．能量最小为10.2eV
ＡＣ
题目分析：处于n=3的能级向较低能级跃迁过程中，有3到2、3到1和2到1三种光子，所以A对B错；能量最大是
="12.09eV" ，能量最小是
="1.89eV" ，所以C对D错。
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