题干

少量铁粉与100ml 0.01mol/L的稀盐酸反应,反应速率太慢。为了加快此反应速率而不改变H2的产量,可以使用如下方法中的(     )
①加H2O ②加NaOH固体 ③滴入几滴浓盐酸 ④加CH3COONa固体
⑤加NaCl溶液 ⑥滴加几滴硫酸铜溶液 ⑦升高温度(不考虑盐酸挥发)
⑧改用10ml 0.1mol/L的盐酸

A:①⑥⑦

B:③⑤⑧

C:③⑦⑧

D:③⑥⑦⑧

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答案(点此获取答案解析)

C

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阅读理解

    Cycling or even walking in city areas can be a little dangerous, thanks to the fact that one is sharing the road with vehicles that are increasingly getting larger and heavier. A recent study proves that of the 1.27million people that die in road traffic crashes each year, about half are walkers, motorcyclists and cyclists. Now there may be a solution that could provide at least some help to protect this helpless group---an airbag!

    If you are worried that this safety measure will involve you taking around a heavy package or worse still, wrapping yourself inside an ugly plastic bag, the bag is fitted not on the human, but on the outside of the vehicle. And, while there are several versions of the idea in the works, the one most recently unveiled by Dutch car company TNO, seems to be the most advanced and ready to go into production.

    In the works since 2011, the airbag covers only the lower part of the windshield. This will provide the much needed buffer(缓冲)between the person's head and the pane of glass he/she would otherwise meet.

    The chain of events leading to an airbag cause are quite simple---A camera fitted beneath the rear-view mirror monitors the vehicle's closeness to a walker or cyclist. Any contact with either one of them sets off the sensors in the car's bumper and quickly blows up the airbag. In addition to that the sensors also set off the car's automatic brake, reducing the chances if an even worse injury.

    In tests conducted using a model, the success of not getting injured after being hit by a car travelling at about 40km/h was about 50-50! While not perfect, it will still result in reducing the number of deaths by a huge amount.

    With TNO ready to license its technology to car makers and many more companies trying to develop similar concepts, we would not be surprised if outer airbags become a standard feature in every car pretty soon.