单项选择题

红外吸收光谱的产生是由于（）
A、分子外层电子能级、振动能级与转动能级的跃迁
B、原子外层电子能级、振动能级与转动能级的跃迁
C、分子振动能级与转动能级的跃迁
D、分子电子能级与振动能级的跃迁

你可能感兴趣的试题

单项选择题

选择合适从句补全对话。甲: Hi, Johnson, you’re looking for a cheap hotel, right? 乙: Yes. Do you have any suggestions? 甲: I saw some news about a youth hostel __1_ yesterday. I think you may be interested in it. It can save you lots of money. 乙: Great! I’ve wanted to find such a hotel _2. Thank you so much. 甲: Tell me more about the island _3. 乙: Sure. But can you take care of my dog _4? 甲: No problem. 第4空选择从句______。
A、while I am away
B、when you come back
C、while I was surfing the Internet
D、since I decided to travel to that island

单项选择题

工程中习惯上将没有明显屈服点的钢筋称为硬钢。
A、正确
B、错误