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问题 填空题

（14分）用18mol/L 浓硫酸配制100 ml 3.0mol/L 稀硫酸的实验步骤如下：

①计算所用浓硫酸的体积  ②量取一定体积的浓硫酸 ③溶解   ④转移、洗涤  ⑤定容、摇匀

回答下列问题

（1）所需浓硫酸的体积是                 ，量取浓硫酸所用的量筒的规格是        

（从下列中选用  A. 10ml   B. 25ml   C. 50ml   D. 100ml）

（2）第③步实验的操作是                                                     

                                                                         

（3）第⑤步实验的操作是                                                     

                                                                        

（4）下列情况对所配制的稀硫酸浓度有何影响？（用偏大、偏小、无影响填写）

A．所用的浓硫酸长时间放置在密封不好的容器中               

B．容量瓶用蒸馏洗涤后残留有少量的水               

C．所用过的烧杯、玻璃棒未洗涤                 

D．定容时俯视溶液的液凹面                    

答案

（1）16.7ml    B （3+1分）

（2）先向烧杯加入30ml 蒸馏水，然后将浓硫酸沿烧杯内壁缓慢倒入烧杯中，并用玻璃棒搅拌。（3分）

（3）继续向容量瓶注入蒸馏水至离刻度线1-2cm处，改出胶头滴管向容量瓶滴加至液凹面与刻度线相切为止。塞紧瓶塞，倒转摇匀。（3分）

（4）A. 偏小   B. 无影响   C. 偏小   D. 偏大（各1分，共4分）

完形填空

Well, to pick up where we left off last time, I believe we agreed that creativity is a mysterious idea. It is those things we all recognize when we see it, but we don’t really understand what it is. We seem to feel that some people are naturally creative, but we don’t know how they got that way. Is creativity a natural gift like good looks, or is it something that can be acquired like knowledge? Perhaps if we analyze the creative process carefully, we might get some insight into what it is and how it might work in our lives. The creative process has always been accepted as the source of all important work in the arts, but we should not think the creativity plays a role only in the arts. Every major scientific discovery began with someone imagining the world to look differently from the way others saw it. And this is what creativity is all about -- imagining the world in a new way. And despite what you may believe about the limits of your own creative imaginations, we all have the potential to imagine the world in an absolutely new way. In fact, you are born with it. It is your birth right as a human being. And what’s more, you use it every day, almost every moment of your life. Your creative imagination is what you use to make sense of your experiences. (Note: Answer the questions or complete the statements in NO MORE THAN 10 WORDS.)

小题1:What did the speaker most probably discuss last time?

__________________________________________________________________

小题2:________________________________ is the widely accepted idea about the creative process.

小题3: ___________________________ leads to major scientific discoveries according to the speaker?

小题4:According to the writer, what is creativity all about?

________________________________________________________________________
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单项选择题

二战后，美国推行“冷战”政策的显著特征是（）

A.遏制 * * 主义，但是不诉诸战争

B.支持希腊政府阻止 * * 党夺权

C.组织北约，加强同苏联抗争的实力

D.帮助欧洲复兴稳定资本主义制度
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