2005年诺贝尔化学奖获得者施罗克等人发现,金属钼的卡宾化合物可以作为非常有效的

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问题:

2005年诺贝尔化学奖获得者施罗克等人发现,金属钼的卡宾化合物可以作为非常有效的烯烃复分解催化剂。工业上冶炼钼的化学原理为(   )

①2MoS2+7O22MoO3+4SO2  ②MoO3+2NH3·H2O=(NH42MoO4+H2O

③(NH42MoO4+2HCl=H2MoO4↓+2NH4C1 ④H2MoO4    MoO3+H2O

⑤用还原剂将MoO3还原成金属钼。则下列说法正确的是

A.反应①和⑤都属于置换反应

B.MoO3属于碱性氧化物

C.在反应①中Mo和S均被氧化

D.利用H2、CO和铝分别还原等量的MoO3,所消耗还原剂的物质的量之比为2:2:3

考点:氧化还原反应与基本反应类型的关系氧化还原反应的本质和特征氧化还原反应的配平氧化还原反应的表示方法
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阅读理解。

     Fish and chips, and Chinese take-away food (熟食) are very popular in England. But they are less

popular (不受欢迎) in the USA. In the USA, they eat take-away food, too, like fried (油炸的)

chicken. But the most popular kind of take-away food is hamburger. It looks like bread with meat in it.

Hamburgers are delicious. They are very popular in the world.

     Chinese food has different tastes and is usually very delicious. It's also very popular in the world.

1. What's the favourite food in the USA?

A. Hamburger.  

B. Fish and chips.

C. Fried chicken.  

D. Take-away food.

2. What does hamburger look like?

A. It looks like a mooncake.          

B. It looks like a sausages (香肠).

C. It looks like bread with meat in it.    

D. It looks like a banana.

3. Which food has different tastes and is usually very delicious?

A. English food.  

B. American food.  

C. Chinese food.  

D. French food.

4. Are fish and chips and Chinese take-away food very popular in the USA?

A. Yes, they are.  

B. No, they aren't.

C. Yes, they were.  

D. No, they weren't.

5. Who do you think likes hamburgers best?

A. The old people.    

B. Children.  

C. Most of the people.    

D. Nobody

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小小百货店每个月的营业成本是12万元.今年上半年月收入分别是:1月份14万元,2月份15万元,3月份11万元,4月份10万元,5月份16万元,6月份11万元.
(1)按照例子填空
小小百货店今年上半年营业盈亏情况表
营业额1月
14万
2月
15万
3月
11万
4月
10万
5月
16万
6月
11万
计数+2万元______________________________
(2)小小百货店今年上半年是______(填盈利或亏损)______(填数字)万元.
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下列哪几项检查可以诊断急性胃黏膜损害?()

A.酶学检查

B.X线检查

C.根据临床表现

D.急诊胃镜检查

E.胃液分析

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徐冰的《生命潭》是一幅______作品。 ( )

A.油画

B.摄影

C.水彩画

D.版画

题型:选择题

《大雅·韩奕》:“无废朕命,夙夜匪解。”诗中出现哪个成语?

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