题干

1000ml某无色待测液中除含有0.2mol•L1的Na+外,还可能含有下列离子中的一种或多种:

阳离子

K+、NH4+、Fe3+、Ba2+

阴离子

Cl、CO32、HCO3、SO42

现进行如下实验操作(所加试剂均过量):(已知:NH4++OH(浓)=NH3↑+H2O)

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同类题2

阅读下面语段, 完成下列小题。

鲁迅自传

    我于一八八一年生于浙江省绍兴府城里的一家姓周的家里。父亲是读书的;母亲姓鲁,乡下人,她以自修得到能够看书的学力。听人说,在我幼小时候,家里还有四五十亩水田,并不很愁生计。但到我十三岁时,我家忽而遭了一场很大的变故,几乎什么也没有了;我寄住在一个亲戚家里,有时还被称为乞食者。我于是决心回家,而我底父亲又生了重病,约有三年多,死去了。我渐至于连极少的学费也无法可想;我底母亲便给我筹办了一点旅费,教我去寻无需学费的学校去,因为我总不肯学做幕友或商人,——这是我乡衰落了的读书人家子弟所常走的两条路。

    其时我是十八岁,便旅行到南京,考入水师学堂了,分在机关科。大约过了半年,我又走出,改进矿路学堂去学开矿。毕业之后,即被派往日本去留学。但待到在东京的预备学校毕业,我已经决意要学医了。原因之一是因为我确知道了新的医学对于日本维新有很大的助力。我于是进了仙台(Sen-dai)医学专门学校,学了两年。这时正值俄日战争,我偶然在电影上看见一个中国人因做侦探而将被斩,因此又觉得在中国医好几个人也无用,还应该有较为广大的运动……先提倡新文艺。我便弃了学籍,再到东京,和几个朋友立了些小计划,但都陆续失败了。我又想往德国去,也失败了。终于,因为我底母亲和几个别的人很希望我有经济上的帮助,我便回到中国来;这时我是二十九岁。

    我一回国,就在浙江杭州的两级师范学堂做化学和生理学教员,第二年就走出,到绍兴中学堂去做教务长,第三年又走出。没有地方可去,想在一个书店去做编译员,到底被拒绝了。但革命也就发生,绍兴光复后,我做了师范学校的校长。革命政府在南京成立,教育部长招我去做部员,移入北京;后来又兼做北京大学、师范大学、女子师范大学的国文系讲师。到一九二六年,有几个学者到段祺瑞政府去告密,说我不好,要捕拿我,我便因了朋友林语堂的帮助逃到厦门,去做厦门大学教授,十二月走出,到广东做了中山大学教授,四月辞职,九月出广东,一直住在上海。

    我在留学时候,只在杂志上登过几篇不好的文章。初做小说是一九一八年,因为一个朋友钱玄同的劝告,做来登在《新青年》上的。这时才用“鲁迅”的笔名(Pen-name);也常用别的名字做一点短论。现在汇印成书的有两本短篇小说集:《呐喊》,《彷徨》。一本论文,一本回忆记,一本散文诗,四本短评。别的,除翻译不计外,印成的又有一本《中国小说史略》,和一本编定的《唐宋传奇集》。

一九三○年五月十六日

同类题5

阅读理解

    A young man wandered through the desert for forty until he reached a beautiful castle at the top of a mountain. There lived the sage that he was looking for.

    With considerable patience, the sage listened attentively to the reason for the boy's visit, but told him that at that moment he did not have time to explain to him the secret of happiness.

    He suggested that the young man take a walk around his palace and come back in two hours' time.

    “However, I want to ask you a favor,” he added, handing the boy a teaspoon, in which he poured two drops of oil. “While you walk, carry this spoon and don't let the oil spill.”

    The young man began to climb up and down the palace staircases, always keeping his eyes fixed on the spoon. At the end of two hours he returned to the presence of the wise man.

    “So,” asked the sage, “did you see the Persian tapestries hanging in my dining room? Did you see the fantastic garden that the Master of Gardeners spent ten years in creating?”

    Embarrassed, the young man admitted that he had seen nothing.

    “So, go back and see the wonders of my world,” said the wise man. “You can't trust a man if you don't know his house.”

    Now more at ease, the young man took the spoon and wandered again through the palace, this time paying attention to all the works of art that hung from the ceilings and walls. He saw the gardens, the mountains all around the palace, and the delicacy of the flowers. Returning to the sage, he reported in detail what he had seen.

    “But where are the two drops of oil that I entrusted to you?” asked the Sage.

    Looking down at the spoon, the young man realized that he had spilled the oil.

     “Well, that is the only advice I have to give you,'' said the sage of sages. “The secret of happiness lies in looking at all the wonders of the world and never forgetting the two drops of oil in the spoon.”