试题与答案

下表所列各组物质中,物质之间通过一步反应,不能实现右图所示转化的是

题型:选择题

题目:

下表所列各组物质中,物质之间通过一步反应,不能实现右图所示转化的是

答案:

答案:C

题目分析:A选项SiO2+2NaOH=Na2SiO3+H2O,Na2SiO3+2HCl=2NaCl+H2SiO3,H2SiO3SiO2+H2O;B、8HNO3+3Cu=3Cu(NO3)2+2NO↑+4H2O,2NO+O2=2NO2,3NO2+H2O=2HNO3+NO;C、Cu(OH)2不能直接转化为Cu;D、NaOH+CO2=NaHCO3,NaHCO3Na2CO3+CO2+H2O,a2CO3+Ca(OH)2=CaCO3+2NaOH

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题型:单项选择题

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根据上述资料,回答以下问题:

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A.明星产品

B.金牛产品

C.问题产品

D.瘦狗产品

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题型:阅读理解

Hello! I’m Alex. I often get up at 6:30 am. Half an hour later(之后), I have my breakfast. At 7:30 am, I take a bus to school. We have Math, Chinese and English classes from 8:00 am to 11: 30 am. I have lunch and talk with my classmates at school. We have three classes from 1:40 to 4:10 in the afternoon. After school, I often play with my classmates. We often play soccer, tennis and ping-pong. I go home at about 5:00 pm. I usually have dinner at 6:00 pm. Then I do my homework and watch TV. At about 10:30 pm, I go to bed.

小题1:---When does Alex go to school in the morning?

--- At______.

A.half past six

B.seven

C.six thirty

D.seven thirty小题2:---What time does Alex eat breakfast?

--- At ______.

A.six

B.seven

C.seven thirty

D.eight小题3:How long does it take Alex to have breakfast?

A.Thirty minutes

B.An hour

C.Ten minutes

D.Seven hours小题4:Alex usually ______before he goes to bed.

A.plays computer games

B.takes a shower

C.play soccer

D.watch TV

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