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问题 单项选择题 A1/A2型题

测砷的新银盐法中所用的吸收剂是聚乙烯醇-硝酸银-乙醇溶液，在配制过程的描述中，提出按1+1+2先混合聚乙烯醇溶液和硝酸-硝酸银溶液再加入乙醇，其原因是（）

A.防止聚乙烯醇与乙醇先混合，过高的乙醇浓度导致聚乙烯醇析出

B.防止硝酸银-硝酸与乙醇混合，过高的乙醇浓度与硝酸产生激烈反应

C.防止硝酸银-硝酸与乙醇混合，过高的乙醇浓度会使硝酸银析出

D.为了提高聚乙烯醇-硝酸银反应中聚乙烯醇的浓度

E.硝酸-硝酸银溶液与乙醇混合后会出现分层

答案

参考答案：A

阅读理解

  Look! There are thousands of people waiting to buy tickets home in the railway station．Each time when Spring Festival comes，buying tickets of train trip would be very hard．And things seem to be getting worse and worse，although we have greatly increased the mileage(总里程) of railway network and speeded up trains．Why? It’s because too many people want to go back home to spend Spring Festival with their family．Many people become angry with the Ministry(部)of Railways．They wonder why it is hopeless for them to get the tickets from the railway station．Instead，they sometimes can only buy them from ticket scalpers at much higher price．

The Ministry of Railways estimated(估计) that about 216 million passengers would travel by train during the 40-day peak period(高峰期) during the 2010 Spring Festival holiday．The number of travelers will be 8％higher than that of 2009．This problem even attracted the President Hu Jintao’s attention．He wrote a note to Liu Zhijun，Minister of the Ministry of Railways，asking him to make sure of a “smooth and safe” transportation．Afterwards，officials from the Ministry of Railways said they would try their best not to let any ticket-buyers spend Spring Festival at the railway station．

小题1: What does the underlined word “scalper” in the first paragraph mean?

A．代售点

B．售票员

C．票贩

D．赌徒小题2: Many people can’t buy the tickets from the railway station，and they sometimes can only buy them from the scalpers        ．

A．expensively

B．wrongly

C．dangerously

D．hardly小题3:How many people took the train trip during the peak period during the 2009 Spring Festival holiday?

A．About 216 million．

B．About 172 million．

C．About 200 million．

D．About 233 million．小题4:What does the passage mainly tell us?

A．People go home much more easily during the Spring Festival．

B．It is very hard to buy tickets in the railway station during the Spring Festival．

C．President Hu Jintao cares about the railway building problem．

D．The Ministry of Railways felt sorry about the problem．
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单项选择题

在高三复习阶段每天都有诸多的学习任务等待我们去完成，这常常让我们手忙脚乱。如果善于按照下图所示对我们的学习任务进行管理，并按一定的顺序完成任务，就会大大提高学习的效率。这种做法主要体现了I指重要且紧急的事Ⅱ指重要但不紧急的事Ⅲ指不重要但紧急的事Ⅳ指不重要也不紧急的事（）

A.矛盾普遍性原理

B.主次矛盾关系原理

C.矛盾的主次方面关系原理

D.矛盾的普遍性与特殊性原理
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