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问题 选择题

下列各组物质的水溶液不用试剂无法鉴别出来的是（     ）

A．NaOH、AlCl3

B．CuSO4、BaCl2

C．NaAlO2、HCl

D．MgCl2、AlCl3

答案

答案：D

A可以，氢氧化钠溶液中滴加氯化铝先无沉淀后有沉淀，而氯化铝溶液中加入氢氧化钠溶液先有沉淀后沉淀消失；B可以，硫酸铜溶液为蓝色溶液，氯化钡溶液为无色溶液；C可以，偏铝酸钠溶液中加入HCL先有沉淀后沉淀溶解，而HCL中加入偏铝酸钠溶液先无沉淀后有沉淀产生；D不能鉴别；

听力题

小题1:At last, she _____________she was lost(意识到).

小题2:They all shouted with___________________(激动).

小题3:The old soldier often tell us his _____(经历) in the past.

小题4:Riding a bike has more _____ (优势) than driving a car because of the heavy traffic.

小题5:My father _____ (放松) himself at the weekend.

小题6:They are _____ to see each other .(please)

小题7:Eating ______ is good for us. We must eat more vegetables. (health)

小题8:Look at her ______ (color) face. She must be badly ill.

小题9:We are celebrating my parents’ 20 years of _________________(marry)

小题10:His father’s ______ made them feel sad.(die)
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多项选择题

金融期货一经产生便得到迅速发展。这种发展具体表现在( )。

A．期货投资者数量的急速增加

B．金融期货种类的发展

C．金融期货市场的发展

D．金融期货交易规模的发展
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