题干

通过加入过量的化学药品,采用恰当的分离混合物的方法,除去某溶液里溶解着的杂质,下列做法中正确的是(括号内的物质为杂质)(  )

A:NaCl溶液(BaCl2).加Na2SO4溶液,过滤

B:KNO3溶液(AgNO3).加NaCl溶液,过滤

C:NaCl溶液(I2).加酒精,分液

D:KNO3溶液(I2).加四氯化碳,分液

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答案(点此获取答案解析)

D

同类题4

阅读下文,回答问题

    ①那个微凉的午后,门铃突然响了,邮递员将一封普通的信件递至我手中,转身离去。

    ②拆开信封一看,里面有两张信纸,一张上面只是写着零星的几个不规则的字——老师,我想做您的学生;另一张是密密麻麻的成人字迹,意思是他的孩子先天性视弱,只能艰难地看见很近很近的事物,因此在学校里常被同学们嘲笑,孩子虽小,但懂事,受了委屈不说,只是一个人偷偷哭泣。家长为保护孩子的自尊心便让她退学在家了,可孩子实在喜欢读书,于是,家长经别人介绍,给我写了这封信,请求我能单独给她辅导功课。

    ③看着那些雀跃在泛黄信纸上的深情字语,再看看孩子那稚嫩的字迹,我似乎看见家长那期许的目光和孩子趴在桌上,头努力低着,一笔一画在信纸上写字的情景。心被濡湿,倏然难过起来。我拿出手机,拨打信件上的电话号码,允诺免费帮他孩子复习功课。

    ④春风轻拂的周末,我见到了我的这位学生——一个非常拘谨而有礼貌的女孩子。扎着马尾辫,穿着整齐干净的衣服,笑起来,脸颊两边露出两个浅浅的酒窝。也许因为知道自己视力不好,总是微微低着头,似乎显得有些自卑。

    ⑤第一次见面,我没有直接给她补习功课,而是给她讲了许多童话故事,以此来增进我与她之间的感情,好进一步了解她。她听得非常认真,回答问题也很积极。一个小时瞬间而过,最后我让她从前面的几个故事里,随意抽取一个关键词造句。她选择了“撒谎”一词,然后思考了两分多钟,一字一顿地说:“月亮,是一个会撒谎的孩子。”说完她握着小手,似乎非常期待着我的肯定。

    ⑥这一句话,确实是我所未想到的,把月亮比拟成孩子,可以。但为什么会“撒谎”?句子应该还没完整啊。我一时不知如何回答,于是沉默了一会儿说:“再认真想想噢,老师下次上课告诉你答案。”

    ⑦走在回去的路上,脑子里反复回想着刚才的那一幕——离开的时候,我似乎看见她眼角有泪。想到眼泪,我恍然大悟:对啊,她是个视弱的孩子,只能非常艰难地看到眼前的景物,而月亮,或圆或缺,她又怎能知晓?她只能从书本上或别人口中知道月亮的形状,有人说它像一艘弯弯的船,而有人却告诉她那是圆圆的满月。既然她从未看过月亮,而月亮却又在变化,她便自然觉得它就是一个会撒谎的孩子。如此想着,我自责不已,她的造句是想让我这位老师告诉她困惑在她心中已久的确切的答案,我的回答,却如一阵冰冷的风,让她原本生机勃勃的春天迎来阴霾寒冷的冬日。

    ⑧第二天在学校上课,我拿她的造句“月亮,是个会撒谎的孩子”问学生们是否正确,一大半的学生都否定了这个句子,可当我将女孩的故事陈述给他们听时,那些幼小善良的心灵一下子便被感动填满,恳求我带他们去见这位女孩子。

    ⑨当我的40多个学生排成一排,依次出现在女孩家里,并说着“月亮是个会撒谎的孩子”的造句真美时,女孩愣住了,然后冲上来,抱住我,哭了。她说,从来没有人对我这么好。最后学生们相拥一起,强烈要求女孩跟他们一同到我们的学校上学读书,做形影不离的好朋友。女孩允诺了,那是她第一次,抬起头,正视我们。那浅浅的酒窝里,绽放出一朵灿烂的自信之花。

    ⑩数日后,我收到了女孩家长的来信:“孩子从未见过月亮,也看不见,但是,老师您却在她心中勾勒出一轮美丽的月亮。相信,那皎洁的月亮,会让她走出迷顿、困惑与自卑的时光………”

    ⑪读完信,心中徜徉着一种温暖的幸福感。是啊,月亮是个会撒谎的孩子,这是我听过的世上最动人的句子。

同类题5

任务型阅读

    Success seems to find Maya Moore everywhere she goes. But life hasn't been a bed of roses for Maya and her biggest supporter, her mother.____

    Maya discovered her love of basketball in 1997 at the age of 8. That was the year the WNBA (Women's National Basketball Association) began holding games. The young girl watched WNBA star Cynthia Cooper play in Olympics.____

    Three years later her mother, Kathryn, was offered a better job in North Carolina. Kathryn decided to make the move from Missouri because North Carolina provided greater basketball opportunities. Sadly, in under two months the company downsized, and Kathryn lost her job. She remembers, “____” Maya says the difficulties brought them closer, and she praises her mom. “She's more than a teammate. I know she's going to be on my side.”

    About a year later, mother and daughter moved to Georgia, where Maya continued to play basketball. In high school she had the opportunity to play basketball against some of the nation's best players.____ Maya led her team to 125 victories and three state championships. During this time, she was named the national player of the year twice.

    ____ Maya and her mother approached the college decision like they did everything. With careful consideration, Maya chose the University of Connecticut.

A. It was a bad time.

B. It really a competitive skill.

C. The competition improved her skills.

D. You can't succeed without too much payment.

E. The path to success required a lot of hard work.

F. Maya dreamed to compete in the Olympics one day.

G. Universities compared to invite her to join their teams.