题干

下列关于分子、原子、离子构成物质的说法中,不正确的是(   )

A:汞原子聚集成金属汞

B:氢原子结合成氢气

C:氯原子和氢原子结合成氯化氢分子,氯化氢分子聚集成氯化氢

D:氯原子和钠原子分别得、失电子形成氯离子和钠离子,两种离子结合成氯化钠

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B

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    Siri is an artificial intelligence (AI) that you can carry around in the pocket, where it waits patiently to be told what to do. In the week we spend together, my AI assistant has performed admirably in finding me restaurants, or the location of the nearest coffee shop.

    A typical command might be: “Reserve a table for two at a good French restaurant in San Francisco.” Siri responds by presenting a list of top-rated restaurants that can be booked on OpenTable.com. If you say which time you want, it can book you a table without your lifting a finger. In some ways Siri is just a fancy program to the 35 websites it can connect to, from taxi booking websites to movie review databases (数据库). But what's new is the way it can analyze the intentions of its users and use those sites to put them into action.

    Siri attaches possibilities to the explanation of each word and compare your location with other data, some of which you must provide yourself. To send email reminders, Siri obviously needs to know your email address. To “find me the flower shop closest to work”, it needs to know where you work. To pay bills or buy airline tickets, it would need to be linked to your credit card.

    That raises the question of how far we are willing to trust a piece of software that can go and do things for us based on what it “thinks” we mean. Siri may be simple, and always shows its explanation of a command before carrying it out. But it gives users a preview of a new balance between privacy, trust and convenience that the expansion of AI into everyday life is likely to develop.