题干

请你参与实验室用生石灰制取氢氧化钠固体的研究。将一定量的生石灰加入一只洁净的烧杯中,加入碳酸钠溶液,充分反应后冷却到室温,通过过滤、洗涤、干燥得到固体A和溶液B,请回答以下问题。

【查阅资料】NaOH 、Ca(OH)2的溶解度

温度(℃)

0

20

40

60

80

100

NaOH的溶解度(g/100g水)

42

109

129

174

314

347

Ca(OH)2的溶解度(g/100g水)

0.18

0.16

0.14

0.12

0.09

0.07

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Living places

The home of the elephant is in the deep forest. It is the largest of all land animals, and is found both in Asia and Africa. One of the main places in Asia where the elephant lives is the island of Ceylon. The huge forests on the island become the home of thousands of elephants. The trees grow thick and tall. They make many parts almost dark, while bright sunlight is above and around them.

Living habits

The elephant likes the deep part and the coolest places of the forest. There he will stand swinging his ears, to drive away the flies; or he will pull down a branch (树枝) from a tree to fan himself. He likes bathing, and to be near a lake or running water. There he takes in the water with his trunk, and spreads it all over his body.

Food

The elephant enjoys the fruits in the forest, and also the leaves of the trees. There is plenty of food for him in the forests, though he is not always happy with what he finds there.

Way of movement

When a group of elephants moves about in the forest, the oldest goes first. The young elephants and their mothers are in the middle, where they are safest. Then all move along with a great noise, the branches of the trees bending and breaking before them. Though the elephant is usually harmless, no one dares to attack (袭击) a group of them moving through the forest.

How people treat them

In Asia the elephant is trained to work. At one time the African elephant also was trained. Soldiers in ancient times often went to fight on the backs of African elephants. But now the elephant that lives in Africa is illegally (非法地) hunted mainly for its valuable ivory. In order to protect them, governments around the world have developed laws to stop this.

同类题3

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    第一要敬业。敬字为古圣贤教人做人最简易、直捷的法门,可惜被后来有些人说得太精微,倒变得不适实用了。惟有朱子解得最好,他说:“主一无适便是敬。”用现在的话讲,凡做一件事,便忠于一件事,将全副精力集中到这事上头,一点不旁骛,便是敬。业有什么可敬呢?为什么该敬呢?人类一面为生活而劳动,一面也是为劳动而生活。人类既不是上帝特地制来充当消化面包的机器,自然该各人因自己的地位和才力,认定一件事去做。凡可以名为一件事的,其性质都是可敬。当大总统是一件事,拉黄包车也是一件事。事的名称,从俗人眼里看来,有高下;事的性质,从学理上解剖起来,并没有高下。只要当大总统的人,信得过我可以当大总统才去当,实实在在把总统当做一件正经事来做;拉黄包车的人,信得过我可以拉黄包车才去拉,实实在在把拉车当做一件正经事来做,便是人生合理的生活。这叫做职业的神圣。凡职业没有不是神圣的,所以凡职业没有不是可敬的。惟其如此,所以我们对于各种职业,没有什么分别拣择。总之,人生在世,是要天天劳作的。劳作便是功德,不劳作便是罪恶。至于我该做哪一种劳作呢?全看我的才能何如,境地何如。因自己的才能、境地,做一种劳作做到圆满,便是天地间第一等人。

    怎样才能把一种劳作做到圆满呢?惟一的秘诀就是忠实,忠实从心理上发出来的便是敬。《庄子》记佝偻丈人承蜩的故事,说道:“虽天地之大,万物之多,而惟吾蜩翼之知。”凡做一件事,便把这件事看做我的生命,无论别的什么好处,到底不肯牺牲我现做的事来和他交换。我信得过我当木匠的做成一张好桌子,和你们当政治家的建设成一个共和国家同一价值;我信得过我当挑粪的把马桶收拾得干净,和你们当军人的打胜一支压境的敌军同一价值。大家同是替社会做事,你不必羡慕我,我不必羡慕你。怕的是我这件事做得不妥当,便对不起这一天里头所吃的饭。所以我做这事的时候,丝毫不肯分心到事外。曾文正说:“坐这山,望那山,一事无成。”一个人对于自己的职业不敬,从学理方面说,便亵渎职业之神圣;从事实方面说,一定把事情做糟了,结果自己害自己。所以敬业主义,于人生最为必要,又于人生最为有利。庄子说:“用志不分,乃凝于神。”孔子说:“素其位而行,不愿乎其外。”我说的敬业,不外这些道理。