题目内容

【题目】关于原子轨道的说法正确的是( )

A.凡是中心原子采取sp3杂化轨道成键的分子其立体构型都是正四面体形

B.CH4分子中的sp3杂化轨道是由4个氢原子的1s 轨道和碳原子的2p轨道杂化而形成的

C.sp3杂化轨道是由同一个原子中能量相近的s 轨道和p轨道杂化形成的一组能量相近的新轨道

D.凡AB3型的共价化合物,其中心原子A均采用sp3杂化轨道成键

【答案】C

【解析】中心原子采取sp3杂化,四个sp3杂化轨道在空间的形状是正四面体形,但如果中心原子上还有孤电子对,分子的立体构型就不是正四面体形。CH4分子中的sp3杂化轨道是碳原子的一个2s轨道与三个2p轨道杂化而成的。AB3型的共价化合物,A原子可能采取sp2杂化或sp3杂化。

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B组

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C组

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【2】Think of the answers you want to give. Although you will never completely know in advance every question they will ask you, there are questions that get asked in almost every interview. Learn what they are and try to predict what the others might be. Interview questions are usually sourced from the job posting. If they are looking for a particular skill set, make sure you can explain how you will meet that expectation.

【3】Do your best to get information about the company before the interview. Do some research, such as using their website, scanning through annual reports if they publish one, being familiar with the project they are now working on. This will help you to present your answers in the context of what their core business is about.

【4】Most job postings have a list of core duties or responsibilities as well as what qualifications are required. Study these well and prepare your answers accordingly. Think about what education and training you have had and what work experiences you have done that makes you the ideal person for the position. Be thorough in your self-assessment, think broadly about all you have learned and experienced. You may surprise yourself with what skills you have acquired previously.

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【题目】完成句子

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【题目】A

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