题干

20℃时,在三个各盛有100g水的容器中分别加入甲、乙、丙三种纯净物(不含结晶水,不与水反应)各10g,充分溶解后,情况如下表所示 ,下列有关说法不正确的是(   )

物      质

未溶解固体的质量/g

7

0

3

A:所得溶液可能都是饱和溶液

B:三溶液中溶质的质量分数乙>丙>甲

C:升高温度,三种溶液中溶质的质量分数一定会改变

D:20℃时,甲的溶解度最小

上一题 下一题 0.0难度 选择题 更新时间:2016-12-20 04:05:58

答案(点此获取答案解析)

C

同类题3

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    How to Say Goodbye

    Knowing how and when to say goodbye is often difficult, even in informal situations. But learning to say goodbye appropriately is a skill that will help you keep your relationships and let people know you care.____ Read on to learn how to recognize opportunities when you leave.

    ____

    When you're at any kind of party or gathering, or even a one-on-one conversation, it can be difficult to get away. Learning to recognize good opportunities to leave will make a short-term goodbye much easier.

Watch body language.

    People don't like telling you that they'd like you to leave.____ If the host of a party starts cleaning up, or withdraws (退出) from the conversation, gather your friends or belongings and make your exit. If someone starts checking their watch, or seems otherwise restless, it's also time to leave.

    Make plans to see each other again.

    Even saying, “See you at school tomorrow,” or “Can't wait to see you again at Christmas” keeps the goodbye light and focused forward.____

Tell the truth.

    Many people expect to come up with a “good excuse” when they're ready to leave.____If you want to leave, just say, “I'm going to go now, see you later.”

A. You don't need to.

B. Set up a coffee date.

C. Recognize when to leave.

D. So try and watch for signals.

E. It makes the goodbye easier.

F. It's also easier than it seems sometimes.

G. If you haven't already made plans, use it as an opportunity to make them.