题干

汽车尾气中的CO在四氧化三钴(Co3O4)纳米棒的催化作用下,低温即与O2反应生成CO2.下列关于该反应的说法中错误的是(   )

A:该反应可降低汽车尾气对大气的污染

B:反应后碳元素的化合价升高

C:该反应中Co3O4反应前后质量减少

D:该反应类型为化合反应

上一题 下一题 0.0难度 选择题 更新时间:2019-11-19 03:53:16

答案(点此获取答案解析)

C

同类题2

阅读理解

    BEIJING — The launch of a new manned space mission brings China closer to the establishment of a permanent space station, international experts say.

    Chinese taikonauts, Jing Haipeng, 50, and Chen Dong, 37, were blasted off into space onboard Shenzhou-11 at 7:30 am Monday and will spend 30 days in the Chinese space laboratory Tiangong-2.The launch marks a key step toward China's plan to eventually operate a permanent space station. The successful launch of the Shenzhou-11 spacecraft is another step forward to put China among leading players in space technology, said Alexander Zheleznyakov, a Russian expert on history of space flights. China's experimental space lab will help provide solutions for spacecraft of different functions to approach and anchor, and for a long-term operation of life support system, said Zheleznyakov. Shenzhou-11 is scheduled to anchor on Wednesday with Tiangong-2, which is part of China's plan to build a permanent space station by 2022.

    China can now test technologies for cargo spacecraft anchoring, life support system operation and water recycling to ensure a long-term continuous operation of its space station in the future with less dependence on renewal from the Earth, he said. If all goes well, China will launch the unpiloted Tianzhou-1 cargo ship next spring to autonomously tie up with Tiangong-2. Tianzhou-1 will be capable of automatically transferring rocket fuels, a vital requirement for space station grouping and maintenance, according to a report by Columbia Broadcasting System (CBS).

    "That will further their anchoring abilities needed for the larger space station," Johnson Freese was quoted." Tiangong-2 is supposed to be able to stay in orbit for two years or longer, so that's taking them (Chinese) really close to 2019 or so. I think this will be their last big technology test phase before going to their large space station," said Freese.