问题 选择题

下列各组物质中能利用右图装置进行实验制取气体的是(  )

(1)用硫酸铜固体和5%的过氧化氢溶液制取氧气

(2)二氧化锰固体和5%的过氧化氢溶液制取氧气

(3)二氧化锰固体和氯酸钾溶液制取氧气

(4)锌片和稀硫酸制取氢气.

A.仅(1)(2)

B.仅(3)(4)

C.仅(1)(2)(4)

D.仅(1)(3)(4)

答案

(1)原题装置适合于固体和液体在常温下反应且生成的气体难溶(或不易溶)于水,而硫酸铜固体和5%的过氧化氢溶液制取氧气,符合要求;故正确.

    (2)二氧化锰固体和5%的过氧化氢溶液制取氧气适合原题装置要求;故正确.

    (3)二氧化锰固体和氯酸钾溶液制取氧气适合于固体和固体需要加热的反应装置,故不正确.

    (4)锌片和稀硫酸制取氢气适合原题装置要求.故正确.

故选C

单项选择题
阅读理解

Our quarrel with efficiency is not that it gets things done, but that it is a thief of time when it leaves us no leisure to enjoy ourselves, and that it strains our nerves when we try to get things done perfectly. In building bridges, American engineers calculate so finely and exactly as to make the two ends come together within one-tenth of an inch. But when two Chinese begin to dig a tunnel from both sides of a mountain both come out on the other side. --The Chinese’s firm belief is that it doesn’t matter so long as a tunnel is dug through, and if we have two instead of one, why, we have a double track to boot.

  The pace of modern industrial life forbids this kind of glorious and magnificent idling. But, worse than that, it imposes upon us a different conception of time as measured by the clock and eventually turns the human being into a clock himself. (This sort of thing is bound to come to China, as is evident, for instance, in the case of a factory of twenty thousand workers. The luxurious prospect of twenty thousand workers coming in at their own sweet pleasure at all hours is, of course, somewhat terrifying.)Nevertheless, such efficiency is what makes life so hard and full of excitement. A man who has to be punctually at a certain place at five o’clock has the whole afternoon from one to five ruined for him already. Every American adult is arranging his time on the pattern of the schoolboy - three o’clock for this, five o’clock for that, six-thirty for change of dress, six-fifty for entering the taxi, and seven o’clock for arriving at the destination. It just makes life not worth living.

小题1:The writer objects to efficiency mainly on the grounds that it ____.

A.gives us rights to have too much leisure time

B.urges us to get things done punctually

C.robs us of leisure time

D.imposes on us a perfect concept of time小题2: In the eyes of the author, the introduction of industrial life gives rise to ____.

A.the excitement of life

B.magnificent idling of time

C.more emphasis on efficiency

D.terrifying schoolboy小题3:The passage tells us ____.

A.Chinese workers come to work when it is convenient

B.all Americans are forced to be efficient against their will

C.Chinese engineers are on better terms with the management

D.Americans ought not to work so hard for efficiency小题4: The author believes that relaxing the rule of punctuality in factories would lead to ____.

A.great trouble

B.increased production

C.a hard and exciting life

D.successful completion of a tunnel