题干

下列描述违背化学原理的是( )

A:碳酸钠溶液显碱性,硫酸钠溶液显中性,可判断硫与碳的非金属活动性强弱

B:相同温度时,取物质的量浓度相同的盐酸和乙酸分别滴在PH试纸上,可判断
两者酸性强弱

C:NH4Cl溶于重水(D2O)中,反应生成的一水合氨和水合氢离子分别为NH3·HDO和等D3O+

D:高温时C能置换出SiO2中的Si,说明还原性C比Si强

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答案(点此获取答案解析)

D

同类题3

阅读下面材料, 从每题所给的A, B, C, D四个选项中选出最佳选项。

(C )

    A major development to self-driving cars may change the way we will drive in the future. Google, the leading company in self-driving technology, has changed its develop plan. It had driverless cars built by car factories, but now it will start building its own cars.

    Google has started to build some kinds of experimental electric self- driving cars that look like a Smart car or Fiat 500. There is no steering wheel(方向盘), gas pedal or brake. The only things a human passenger controls are a red "e-stop" button (按钮) for fear stops and a start button. The car's only "friendly" face is designed to make it help people accept self-driving technology.

    Google workers took part in a long experiment, in which they used self-driving cars for their usual travel to work. No accident happened, but Google's heads realized that depending on a human passenger to drive in an emergency(紧急情况) wouldn't work because they may be reading, working , or sleeping. Now the self-driving car drives by itself if the driver takes his hands off the wheel for over ten seconds.

    Google recently announced that its cars had covered 700,000 miles of public roads, and they were now running in busy city streets. People who love self-driving cars say this will improve transport by making roads safer, cutting down accident, and making less pollution.

    Of course, there's no need to look for parking at a crowded shopping mall. Instead, users could let their self-driving cars drop them off to park itself. A mother who took a test ride said that having the car would allow her more time to catch up with her son. The cars could also allow people who might not be able to drive to enjoy the hand-free driving. And drunk driving? Not a problem. It is very likely that by 2020, driverless cars will be common. Do you believe so?