题干

实验室进行科学研究的重要手段,实验方案的设计是实验成功的基本保证,下列实验方案设计不合理的是(   )

选项

实验目的

试验方法

A

区分羊毛和棉花

灼烧并闻气味

B

鉴别NH4Cl和KCl

加熟石灰研磨,闻气味

C

除去CO中混有的CO2

将混合气体通过灼热的氧化铜粉末

D

比较Fe、Cu和Ag的金属活动性

将Fe和Ag分别加入CuSO4溶液中

A:A  

B:B  

C:C  

D:D

上一题 下一题 0.0难度 选择题 更新时间:2018-12-04 03:31:17

答案(点此获取答案解析)

C

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    Nothing succeeds like confidence. When you are truly confident, it radiates from you like sunlight, and attracts success to you like a magnet(磁铁)____ And gaining the confidence of others is one of the key ways in which a self-confident person finds success.

    So how can we build a sense of self-confidence and prepare ourselves on the way to success? First, do what you believe to be right, even if others laugh at you for it____If you believe you can, then you really will. The belief keeps you searching for answers, which means that pretty soon you will get them.

    Second, govern your behavior based on what other people think. What's more important, be willing to take risks and go the extra miles to achieve better results, in which case mistakes can not be avoided____  Next, work hard to settle the problems in order to cover up your mistakes before anyone notices. Building self-confidence is readily achievable, as long as you have the focus and determination to carry things through.

    With your determination and improvement, you are getting closer to success. At this stage, wait for others to congratulate you on your accomplishments. “Thanks, I really worked hard on the road to success. I'm pleased you recognize my efforts.____Self-confidence is extremely important in almost every aspect of our lives, and it is no wonder that so many people struggle to find it____ Besides, whether you're working on your own self-confidence or building the confidence of people around you, it's well worth the effort!

A. Believe in yourself and believe that you can do it under any circumstances.

B. Highly self-confidence person can achieve great results in every field he enters.

C. Besides, those who are self-confident can in turn inspire confidence in others.

D. The congratulations from others will promote you to gain further success.

E. Self-confidence really can be learned and built on.

F. Don't hesitate to admit your mistakes, and learn from them.

G. A lack of confidence can lead to a lot of sufferings.