题干

小黄用如图装置测定铜锌合金中锌的质量分数和锌的相对原子质量。主要实验步骤如下(必要的固定装置已略去)。

①连接装置并检查装置气密性;

②加入药品和水;

③记录C中液面刻度(C为带有刻度的玻璃管); 

④由A向B中滴加试剂至过量;

⑤待B中不再有气体产生并恢复至室温后,记录C中液面刻度,计算得到气体的体积为V mL(该气体密度为ρg/L;

⑥将B中剩余固体过滤、洗涤、干燥并称重,称得剩余固体质量为W g

根据题意完成下列问题。

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同类题4

根据短文内容,选择最佳答案。

    In the United States, when one becomes rich, he wants people to know it. And even if he does not become very rich, he wants people to think that he is. That is what “keeping up with the Joneses” is about. It is the story of someone who tried to look as rich as his neighbors.

    The expression was first used in 1913 by a young American called Arthur Momand. He told this story about himself. He began earning $ 125 a week at the age of 23. That was a lot of money in those days. He got married and moved with his wife to a very wealthy neighborhood outside New York City. When he saw that rich people rode horses, Momand went horseback riding every day. When he saw that rich people had servants, Momand and his wife also hired a servant and gave big parties for their new neighbors.

    It was like a race, but one could never finish his race because one was always trying to keep up. The race ended for Momand and his wife when they could no longer pay for their new way of life. They moved back to an apartment in New York City.

    Momand looked around him and noticed that many people do things just to keep up with rich lifestyle of their neighbors. He saw the funny side of it and started to write a series of short stories. He called it “Keeping up with the Joneses” because “Jones” is a very common name in the United States. “Keeping up with the Joneses” came to mean keeping up with rich lifestyle of the people around you. Momand's series appeared in different newspapers across the country for over 28 years.

    People never seem to get tired of keeping up with the Joneses. And there are “Joneses” in every city of the world. But one must get tired of trying to keep up with the Joneses because no matter what one does, Mr. Jones always seems to be ahead.

同类题5

阅读下面的文言文,完成后面小题。

    凡兵,不攻无过之城,不杀无罪之人。夫杀人之父兄,利人之货财,臣妾人之子女,此皆盗也。故兵者,所以诛暴乱、禁不义也。兵之,所加者,农不离其田业,贾不离其肆宅,士大夫不离其官府。由其武议在于一人,故兵不血刃而天下亲焉。

    夫将,提鼓挥袍,临难决战。接兵角刃,鼓之而当,则赏功立名;鼓之而不当,则身死国亡。是存亡安危在于袍端,奈何无重将也。

    武王伐纣,师渡盟津,右旄左钺,死士三百,战士三万。纣之陈亿万,飞廉、恶来身先戟斧,开百里。武王不罢士民,兵不血刃而克商诛纣,无祥异也,人事修不修而然也。今世将合龟兆,视吉凶,观星辰风云之变,欲以成胜立功,臣以为难。

    胜兵似水夫水至柔弱者也然所触丘陵必为之崩无异也性专而触诚也。今以莫邪之利,犀兕之坚,三军之众有所奇正①,则天下莫其战矣。故日:举贤用能,不时日而事利;明法审令,不占筮而获吉;贵功养劳,不祷祠而得福。又曰:天时不如地利,地利不如人和。古之圣人谨人事而已。

吴起与秦战,不平陇亩,朴樕②盖之以蔽霜露。如此何也?不自高人故也。乞人之死不索尊,竭人之力不责礼。故古者甲胄之士不拜,示人无己烦也。夫烦人而欲乞其死、竭其力,自古至今未尝闻矣。将受命之日忘其家,张军宿野忘其亲,袍而鼓忘其身。吴起临战,左右进剑。起日:“将专主旗鼓尔,临难决疑,挥兵指刃,此将事也。一剑之任,非将事也。”三军成行,一舍而后成三舍,三舍之余,如决川源。望敌在前,因其所长而用之。敌白者垩之,  赤者赭之。吴起与秦战,未合,一夫不胜其勇,前获双首而还。吴起立斩之。军吏谏日:“此材士也,不可斩。"起日:“材士则是也,非吾令也。”斩之。

【注】①奇正:古代兵法术语。古代作战以对阵交锋为正,设计邀截、袭击为奇。②朴樕:一种灌木类的小树,泛指树枝。

(节选自《尉缭子》)