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    Like all big cities, Paris has a traffic problem: lots of cars, lots of traffic jams and lots of pollution from exhaust fumes (废气). So the city began a project to improve the situation.

    Under the Velib project ('Velib' comes from vélo liberté, or 'bicycle freedom') people can take a bicycle, use it for as long as they want, and then leave it at the same or another bicycle station. The first half-hour on the bike is free, but if you don't return it after 30 minutes, you have to pay. But it's only €1 a day or €29 a year! The bicycles are heavy (25 kg), and they are all grey and have baskets. There are about 20,000 of them in the city, and around 1,450 bicycle stations. So there are a lot more Velib stations than the 298 subway stations!

    Paris is not the first city to have a project like this. But not everybody thinks it's a great idea. One Parisian said, “These bicycles are only for short journeys. If people want to travel across the city, they won't use a bicycle — they'll still use their cars.”

    A city spokesman said, “The bicycle project won't solve all our traffic problems, of course. But it might help reduce air pollution. Traffic, together with factory fumes, is a big problem. There aren't any simple answers to traffic problems and pollution in cities. But unless we do something now, there will be more traffic jams and temperatures will continue to rise, so the problems in our environment will get worse. The bikes might help people to lead a healthier life, too.”

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同类题3

为了减少CO对大气的污染,某学习小组拟研究CO和H2O反应转化为绿色能源H2

(1)已知:2CO(g)+O2(g)═2CO2(g);△H=﹣566kJ•moL﹣1

2H2(g)+O2(g)═2H2O(g);△H=﹣483.6KJ•moL﹣1

H2O (g)═H2O(l);△H=﹣44.0KJ•moL﹣1

写出CO和H2O(g)作用生成CO2和H2的热化学方程式____ 

(2)在850℃时,反应:CO(g)+H2O(g)⇌CO2(g)+H2(g)的K=1.

①:若升高温度到950℃时,达到平衡时K____ 1(填“>”、“<”或“=”).

②:850℃时,若向一容积可变的密闭容器中同时充入1.0mol CO,3.0mol H2O,1.0mol CO2和x mol H2,若要使上述反应开始时向正反应方向进行,则x应满足的条件是____ 

③:在②的条件下,按下列加料方式加料,达到平衡时H2的体积分数如下:


加料方式/mol

H2的体积分数

物质

CO(g)

H2O(g)

CO2(g)

H2(g)

加料一

1

3

0

0

a%

加料二

0

1.2

0.6

0.6

b%

则:a____b(填“>”、“<”或“=”).

(3)H2是一种理想的绿色能源,可作燃料电池.

①若该氢氧燃料电池以KOH为电解质溶液,其正极的电极反应式是____ 

②在25℃时,以氢氧燃料电池为电源,用石墨电极电解1000mL一定浓度的CuSO4溶液.5min后电解完全,在一个石墨电极上只有1.28g Cu生成.试回答下列问题:

电解的总反应式为____ 

电解过程中转移的电子数为____ mol,同时生成标准状况下气体的体积为____ L