题干

原电池产生电流的本质原因是(    )

A:原电池中溶液能电离出自由移动的离子

B:有导线将两个活动性不同的电极连接

C:正极发生了氧化反应,负极发生了还原反应

D:电极上进行的氧化还原反应中有电子的转移

上一题 下一题 0.0难度 选择题 更新时间:2019-05-09 05:43:18

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D

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    The Crowne Plaza Hotel in Copenhagen is offering a free meal to any guest who is able to produce electricity for the hotel on an exercise bike linked to a generator (发电机). The idea is to get people fit and reduce their carbon footprint. Guests will have to produce at least 10 watt hours of electricity — roughly 15 minutes of cycling for someone of average fitness. Guests staying at Plaza Hotel will be given meal tickets worth $ 36 once they have produced 10 watt hours of electricity. The bicycles will have smart phones attached to the handlebars measuring how much power is being generated for the hotel.

    The plan, a world-first, will start on 19 April and run for a year. Only guests staying at the hotel will be able to take part. Frederikke Toemmergaard,hotel spokeswoman, said, “Many of our visitors are business people who enjoy going to the gym. There might be people who will cycle just to get a free meal, but generally I don't think people will take advantage of our programme.”

    Copenhagen has a long-standing cycling tradition and 36 % of locals cycle to work each day, one of the highest percentages in the world, according to the website visitcopenhagen. dk. US environmental website treehugger. com recently voted Copenhagen the world's best city for cyclists. “Because Copenhagen is strongly connected with cycling, we felt the bicycle would work well as a symbol of the hotel's green profile (形象).”

    If successful,the electric bicycle meal programme will be spread to all Crowne Plaza hotels in the UK, the hotel said in a statement.