题干

图中横坐标为加入反应物的物质的量,纵坐标为产生沉淀的物质的量.下列选项编号对应的曲线编号错误的是(   )

A:向NaAlO2溶液中逐渐滴入HCl至过量

B:向含有等物质的量的Ca(OH)2、KOH的混合溶液中通入CO2至过量

C:向澄清石灰水中通入CO2至过量

D:向含有盐酸的AlCl3溶液中滴入NaOH溶液至过量

上一题 下一题 0.0难度 选择题 更新时间:2019-08-10 11:43:40

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C

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    Are you suffering from FOMO—that is, Fear Of Missing Out? Research shows that a growing number of young people are, with worrying reasons for their sleep and schoolwork.

    ____ You aren't able to do your best unless you sleep well. Most experts agree that the optimum(最适宜)number of hours is eight, and this has been accepted as common sense for as long as I can remember. However, I was young once and know most of you get much less sleep than that.

    I read an interesting article in a teachers' magazine recently. ____ Worryingly, the results showed that teenagers are facing a new problem. They may go to bed and get up at appropriate times, but a growing number are waking up in the middle of the night, not to use the bathroom or have a snack, but because of FOMO.

    According to the article, the number of students waking up during the night to check social media is growing. Afraid of missing a comment or opportunity to take part in a chat, teenagers are waking at all times of the night, going online and getting involved. ____

    Experts are worried about this growing trend and the report reveals some worrying statistics: 23% of 12-to 15-year-olds wake up nearly every night to use social media. ____ One in third of the students are constantly tired and unable to function to their full capacity.

    So I'd like to ask you to be responsible when it comes to social media. Switch off your devices at night. The world won't end and your social media will be waiting to greet you in the morning! ____

A. But things are getting out of hand.

B. They did a study of 848 students in Wales.

C. Another 15% wake up at night once a week for the same reason.

D. I give you my word that you won't have missed anything important.

E. All happens when they should be sound asleep.

F. FOMO is the fear that everyone else is having more fun and more excitement than you.

G. Everybody knows how important it is for students to get a good night's sleep every night