合成氨工业生产中所用的α-Fe催化剂的主要成分是FeO、Fe2O3 (1)某Fe

题型:填空题

问题:

合成氨工业生产中所用的α-Fe催化剂的主要成分是FeO、Fe2O3

(1)某FeO、Fe2O3混合物中,铁、氧的物质的量之比为4:5,其中Fe2+与Fe3+物质的量之比为___________。

(2)当催化剂中Fe2+与Fe3+的物质的量之比为1:2时,其催化活性最高,此时铁的氧化物混合物中铁的质量分数为_____________(用小数表示,保留2位小数)。

(3)以Fe2O3为原料制备上述催化剂,可向其中加入适量炭粉,发生如下反应:2Fe2O3十C4FeO十

CO2↑。为制得这种活性最高的催化剂,应向480g Fe2O3粉末中加入炭粉的质量为_________g。

考点:物质的量的有关计算
题型:填空题

A large number of people in the world eat fast food. Whenever you go into a fast food restaurant,you can see lots of people enjoying their meals there. But do you know in which country people like fast food best?

The English people are the world’s biggest fans of fast food,while the French (法国人) are the least interested in quick meals,according to a survey done last year.

The survey of thirteen countries shows 45% of the English people say they can’t give up fast food because it’s delicious. And 44% of Americans and 37% of Canadians say the same.

The French,proud of their delicious and high-class cuisine,don’t like fast food. 81% of them think it is unhealthy,followed by 75% of the Japanese.

How about the Chinese? How often do you have hamburgers or fried chicken? It doesn’t matter whether you like Western fast food or Chinese food. The most important thing is to keep a balanced diet.

小题1:From the survey we know____________ like fast food best.

A.the Chinese

B.the French

C.the Japanese

D.the English小题2:The survey shows____________  of Americans like fast food.

A.37%

B.44%

C.75%

D.81%小题3:According to the survey,some people can’t give up fast food because____________ .

A.it’s cheap

B.it’s safe

C.it’s delicious

D.it’s healthy小题4:The word “cuisine” in the passage means____________ .

A.food

B.house

C.water

D.country小题5:The survey is about____________ .

A.Western countries

B.fast food

C.restaurants in the world

D.Chinese food

题型:填空题

以下何脉不主虚证

A.细脉

B.数脉

C.代脉

D.濡脉

E.伏脉

题型:填空题

不可伸长的轻绳跨过质量不计的滑轮,绳的一端系一质量M=15kg的重物,重物静止于地面上,有一质量m=10kg的猴子从绳的另一端沿绳上爬,如图所示,不计滑轮摩擦,在重物不离开地面的条件下,猴子向上爬的最大加速度为(g取10m/s2

[ ]

A.25m/s2

B.5m/s2

C.10m/s2

D.15m/s2

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变电事故率是如何统计的?

题型:填空题

易风化药物可使胶囊壳(),而易潮解药物可使胶囊壳()。

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