下列电离方程式书写正确的是() A.Na3PO4=3Na++ B.Ba(OH)2

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问题:

下列电离方程式书写正确的是(   )

A.Na3PO4=3Na++

B.Ba(OH)2=Ba2+

C.CH3COOH=CH3COO+H

D.NaHCO3=Na+H

考点:强电解质、弱电解质电解质、非电解质
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阅读短文,根据短文内容选择所给问题的答案。

Rick is a good man. He makes birthday cakes in a store. His cakes are great and have very good prices, so many people buy his cakes. He makes friends with lots of his customers(顾客). They all like him very much. One evening, he wants to go home, but many of his old customers come in. Rick smiles(笑) to them, “I am sorry. It is late today. If you need cakes, please come tomorrow.” One of them takes out a nice cake and says to him, “You make so many great cakes for us. This birthday cake is for you. Happy birthday, Rick.”

小题1:Where does Rick work?

A.At school.

B.In the classroom.

C.In a store.

D.At a party.小题2:When the customers come, Rick _______________.

A. is making cake                  

B. wants to go home     

C. is at home      

小题3:His customers give(给) him ___________.

A. many cakes                 

B. a birthday cake 

C. some vegetables             

小题4:Rick’s customers like him because __________________.

A. his cakes are at a very good price              

B. his cakes are big   

C. he is a good friend 

小题5:The customers come to Rick’s store because ______________.

A. they want to buy cakes          

B. today is Rick’s birthday   

C. Rick asks them to come      

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一种细菌的直径是0.000015米,用科学记数法表示为______米.

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患者男,21岁。右侧肢体抽搐2年,突然昏迷1小时。查体:神志浅昏迷,左侧肢体偏瘫。CT显示右额叶脑内血肿,临床诊断最可能是()。

A.原发性癫痫

B.脑动脉硬化

C.脑动脉瘤

D.脑血管畸形

E.高血压脑出血

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Alpha收益是指来自于投资管理者个人操作水平和技巧有关的高额收益,即超越市场收益部分的超额收益。

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钢轨组可放在道心或枕木头上并进行固定。钢轨组放在枕木头时,新轨组内侧距线路上钢轨外侧不得小于()。

A、100mm

B、150mm

C、200mm

D、300mm

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