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问题 选择题

下列离子方程式中，正确的是（　　）

A．澄清的石灰水与稀盐酸反应Ca2++2OH-+2H+═Ca2++2H2O

B．用氢氧化钡溶液中和硫酸溶液：Ba2++OH-+H++SO42-=H2O+BaSO4↓

C．KI溶液与适量溴水反应：2I-+Br2=I2+2Br-

D．硫酸铝溶液中加入过量氨水Al3++30H-══Al（OH）3↓

答案

A．澄清的石灰水与稀盐酸发生中和反应，反应的离子方程式为OH-+H+═H2O，故A错误；

B．用氢氧化钡溶液中和硫酸溶液反应的离子方程式应为Ba2++2OH-+2H++SO42-=2H2O+BaSO4↓，故B错误；

C．溴水与KI发生置换反应，反应的离子方程式为2I-+Br2=I2+2Br-，故C正确；

D．氨水为弱电解质，应写成化学式，故D错误．

故选C．

完形填空

Over the years I've been teaching kids about a simple___小题1:___ powerful concept ---- the ant philosophy. They have an amazing four-part philosophy.

First, ants never quit. They'll climb over, they'll climb under, and they'll climb around. They keep looking for another way. What a neat(了不起的) philosophy it is to never quit ___小题2:____(look) for a way to get ____小题3:__you're supposed to go! Second, ants think about winter and summer. That's ____小题4:__ important attitude.                                                              

You can't be _小题5:__ naïve(幼稚的) as to think summer will last forever. People who have a little experience are clear about this. So ants are gathering in their winter food in the middle of summer. It’s important to be realistic. You have to think about rocks as you enjoy the sand and sun. Think ahead. The third part is that ants think summer all winter. During the winter, they remind____小题6:___, "This won't last long; we'll soon be out of here." And ____小题7:___the first warm day, the ants are out. If it __小题8:___(turn) cold again, they'll dive back down. But they come out again if it is warm. They can't wait ___小题9:___(get) out. Last, how much will an ant gather during the summer to prepare for the winter? All that it ___小题10:___ (possible) can.

What a great philosophy to have----the ant philosophy：never give up, look ahead, stay positive and do all you can.
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单项选择题

（）是在招聘的过程中最经常使用但是最不成功的。

A.内部刊登招工启事

B.招聘代理机构

C.公司网站

D.招聘会
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