题干

某淡黄色的颗粒状固体,其化学性质比较活泼,在通常状况下能跟许多物质发生化学反应.例如:它与CO2反应时,只生成了Na2CO3和O2,它与稀盐酸反应时,只生成了NaCl、H2O和O2.上课时,老师做了如下实验:

a.取少量的淡黄色的颗粒状固体投入到盛有少量水的试管中,可观察到产生了一种无色无味的气体;

b.再向试管中滴加几滴酚酞试液,可观察到烧杯中溶液变红.

根据实验现象,回答下列问题:

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同类题1

阅读理解

Mr and Mrs Albina, with 64 children, have the world's largest family. Not one of their children is adopted(领养).
When people hear about the Albinas' large family, the first question they ask is, "How is it possible? How can one woman give birth to 64 children in her lifetime?" The answer is simple: Every time Mrs Albina gave birth, she had twins or triplets.
Soon after the Albinas got married the children came quickly, in twos and threes. The first 21 children were boys. Mrs Albina loved her sons, but she wanted a daughter very much.
The Albinas spent the early years in Argentina. Then they decided to move to Chile. To travel from Argentina to Chile, they had to cross the Andes Mountains. Mr and Mrs Albina and their 21 sons made the difficult, two-week joumey on mules. One night there was a terrible snowstorm in the mountains. During the snowstorm, Mrs Albina gave birth to triplets, a boy and-two girls!
The oldest Albina children are in their thirties and forties. They are on their own now, but 18 of the Albina children still live with their parents The family lives in a two-room shack in Colina Chile. The shack has electricity but no toilet or running water. The children wash in a small bowl in the dusty backyard.
At times there is very little food in the Albinas' small house. When there is not enough food for everyone, Mrs Albina makes sure the youngest children do not go hungry. "The smallest eat first, and then the bigger ones. We've always done it that way," she says. Obviously, the Albinas do not have enough money for their big family. Why, then, do they continue to have children?
The Albinas do not use birth control because it is against their religion (宗教).They could let other people take care of their children, but Mrs. Albina will not allow it. "When my two brothers and I were babies," she says,"our mother left us at an orphanage(孤儿院)and never returned. We lived there together until we were five. Then a couple adopted my brothers, and I was left behind. I was heartbroken. I promised myself that when I became a mother, I would never give my children away. Even if I didn't have much money, I would always take care of my children myself." Mrs Albina has kept her promise.

同类题4

阅读文段,回答问题。

父亲的弟弟于勒叔叔,那时候是全家惟一的希望,在这以前则是全家的恐怖。

据说他当初行为不正,糟蹋钱。在穷人家,这是最大的罪恶。在有钱的人家,一个人好玩乐无非算作糊涂荒唐,大家笑嘻嘻地称他一声“花花公子”。在生活困难的人家,一个人要是逼得父母动老本,那就是坏蛋,就是流氓,就是无赖了。于勒叔叔把自己应得的部分遗产吃得一干二净之后,还大大占用了我父亲应得的那一部分。

人们按照当时的惯例,把他送上从哈佛尔到纽约的商船,打发他到美洲去。

我这位于勒叔叔一到那里就做上了不知什么买卖,不久就写信来说,他赚了点钱,并且希望能够赔偿我父亲的损失。这封信使我们家里人深切感动。于勒,大家都认为分文不值的于勒,一下子成了正直的人,有良心的人。

有一位船长又告诉我们,说于勒已经租了一所大店铺,做着一桩很大的买卖。

两年后又接到第二封信,信上说:“亲爱的菲利普,我给你写这封信,免得你担心我的健康。我身体很好,买卖也好。明天我就动身到南美去作长期旅行。也许要好几年不给你写信。如果真不给你写信,你也不必担心。我发了财就会回哈佛尔的。我希望为期不远,那时我们就可以一起快活地过日子了。” 

这封信成了我们家里的福音书,有机会就要拿出来念,见人就拿出来给他看。

果然,10年之久,于勒叔叔没再来信。可是父亲的希望却与日俱增。母亲也常常说:“只要这个好心的于勒一回来,我们境况就不同了。他可真算得一个有办法的人。