题干

据报道,我国拥有完全自主产权的氢氧燃料电池车已在北京奥运会期间为运动员提供服务.某种氢氧燃料电池的电解液为KOH溶液.下列有关该电池的叙述不正确的是(   )

A:正极反应式为:O2+2H2O+4e═4OH

B:工作一段时间后,电解液中KOH的物质的量不变

C:该燃料电池的总反应方程式为:2H2+O2═2H2O

D:该电池工作时每消耗1 mol O2,有2 mol电子转移

上一题 下一题 0.0难度 选择题 更新时间:2015-03-16 07:14:25

答案(点此获取答案解析)

D

同类题4

阅读下列短文, 根据短文中的信息完成文后表格, 每空一词。

      WARNING(警告): Holding a cell phone against your ear or putting it in your pocket may be bad for your health. This sentence is a warning that you’d better not put it close to you when a new phone is bought. Apple company, for example, doesn't want iPhones to come closer to you than 1.5 centimeters; Research In Motion, BlackBerry's producer, recommends 2.5 centimeters.

      If cell phone use can cause health problems, the result will be very serious. Americans spend 2.26 trillion minutes chatting on cell phones every year, which brings $109 billion for the wireless businessmen.

      Devra Davis, an epidemiologist(皮肤病专家)who has worked for the University of Pittsburgh, has published a book about mobile phone radiation(辐射)"Disconnect." Davis studies how often brain cancer happens during different age groups. As a result of mobile phone radiation, she finds that a big increase(增长)in brain cancer in the 20-to-29 age group and a drop for the older people.

      Children are more easily hurt by radiation than grown-ups, Ms. Davis and other scientists point out. But no studies have yet been finished on cell phone radiation and children, she says.

      Henry Lai, a research professor, began lab radiation studies in 1980 and found that mice exposed to(暴露在) radiofrequency(电波频率)radiation had destroyed DNA in their brains.

      Ms. Davis recommends using wired earphones(有线耳机)or the phone's speaker. Children should send text messages rather than call, she said, and pregnant women should keep phones away from their bodies.

It's ____to your health to use cell phones

____from different companies.

● Apple company ____ using cell phones at least 1.5 centimeters.

● Motion, BlackBerry's producer ____ 2.5 centimeters.

The____of research from different areas

● Devra Davis pointed out in the book "Disconnect" that people in the 20-to-29 age are more likely to have brain cancer than older people ____of mobile phone radiation.

● Ms. Davis and other scientists studied that Children are ____ to be hurt by radiation than adults.

● Henry Lai found that ____exposed to(暴露在) radiofrequency(电波频率) radiation had destroyed DNA in their brains.

Ms Davis's____on how to use the cell phone safely

●Children should send text messages ____of call.

 Pregnant women should keep phones away from their bodies.