问题 选择题

如图,能用纵坐标所对应的变化情况来表示的过程是(  )

A.向一定量的烧碱溶液中加入稀盐酸时溶液pH的变化

B.向一定量锌粒中加入稀盐酸时产生气体体积的变化

C.向一定量铜粉中加入硝酸银时固体质量的变化

D.向质量分数为20%的食盐水中加水时溶质质量的变化

答案

A、烧碱溶液PH大于7,加入稀盐酸会不断消耗烧碱,使溶液的碱性减弱PH减小,恰好反应时PH=7再滴加则PH会小于7,故此选项正确.

B、向一定量锌粒中加入稀盐酸时产生气体体积,随不断加入盐酸氢气量会不断增加,直至反应结束,曲线应是先上升再形成一条直线,故此选项错误.

C、由于铜的活动性比银强,故可置换出溶液中的银,由于银的原子量大于铜故固体质量会不断增加,直至反应完全,故此选项错误.

D、此过程是溶液的稀释过程,整个过程中溶质的质量不变,图象会是一条直线,故此选项错误.

故选A

阅读理解

The best tool you can use in communicating with parents is to keep talking to them, no matter what. Strong relationship (关系) depend heavily on keeping the lines of communication open. Try to talk about everyday things with your parents. That doesn’t mean telling them everything. In fact, turn the focus onto them for a change: Ask about their day — just as they do with you.

David, 16, is a senior school student. One evening, after he mentioned at dinner that he was thinking of trying out for the school play, his mom kept asking about it for weeks. And later, it also felt like she was getting too involved (参与) in something he wanted to do himself. Instead of telling his mom how he felt, David decided it would be easier not to tell her anything he was doing in the future.

A good way to get a parent to ask fewer questions is to offer some information on your own. This puts the communication in your hands. The more you keep a parent told about everyday things, the less they need to ask. Communicating everyday things has another advantage: It can show your parents that you’re responsible enough to make good decisions.

It won’t always be easy. You may get frustrated (受挫) at times. But try not to give up. It may take a bit for a parent who is used to making all the decisions to adjust (适合) to the independent-thinking person their child is becoming. Parents also don’t want to see their sons and daughters suffer (受苦) if the choices they make on their own aren’t the “right” ones. To many parents, it seems easier to step in and take control simply because they believe their years of experience put them in a better position to make decisions. If you feel that’s the case (情况) with your parents, talk to them about it.

小题1:The underlined part “turn the focus onto them” probably means ____.

A.talk the things about them

B.have a good time with them

C.show your thanks to them

D.do something good for them小题2:In the third paragraph, you are advised to ____.

A.let your parents know everything about your daily life

B.tell your parents more information before you are asked

C.keep your parents asking you more questions of your things

D.be responsible to help your parents make good decisions小题3:What causes parents to take control of children?

A.They find their children wrong.

B.They do well in almost everything.

C.They think they can make better decisions.

D.They are used to making choices for children.小题4:The main idea of the passage is how to ____.

A.make decisions on your own

B.learn from your parents

C.think carefully for yourself

D.communicate with parents

单项选择题