题干

除去下列物质中的少量杂质(括号内是杂质),所用试剂及方法均正确的是

A:铜粉(碳粉)——在空气中灼烧

B:氯化亚铁溶液(氯化铜)——加过量的铁粉、过滤

C:氢氧化钠(碳酸钠)——加适量的稀盐酸、蒸发

D:二氧化碳(一氧化碳)——通过足量的氢氧化钠溶液、干燥

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答案(点此获取答案解析)

B

同类题3

阅读下文,回答问题

丑娘

    村里没有人不说我娘长得丑,或许是这个缘故,在她嫁给我爸之后,人们先是叫她“丑媳妇”,在生下我们姐弟四个之后,大家都称她为“丑娘”。

    八岁那年,我开始到离家很远的地方去上学。当时我不明白“丑”是什么意思,因为我娘待我特别好。临走的时候,她给我做了一双毛边鞋、一个小书包,书包上面绣着一只小白兔。我依稀记得,把我送到村口时,她流下了眼泪。

    不久后的一件事使我认识了我的母亲。

    一天,学校上体育课,因为舍不得穿娘做的新鞋,我把它脱下来挂在凳子上。老师看见了。他提过鞋子,左看右看,随即又把鞋子举得高高的,兴奋地说:“好漂亮的鞋啊!”说着,又把鞋底端详了半天,数着一层一层粘起的鞋底,足有八层之多,且针脚细密结实,靠脚掌和脚跟的部分都挑上了花。他问我:“你娘一定很漂亮吧?”没等我回答,同村的一个女同学抢了话头:“老师,他娘不漂亮,村里人都叫她‘丑娘’。”

    我仿佛明白了“丑”的意思。

    或许那位女同学的话是对的。我娘长得确实不漂亮,苍白的肤色,瘦得可怕的身材,五官也极不协调。从此,我心里像含着什么委屈,在公开场合很少提及她,更不愿把同学领到家。

    转眼间,我走上了工作岗位,长成了一个大小伙子了,娘更加苍老了,头发变得稀疏而花白。想想娘养我这么大,一辈子在农村吃苦,且面对别人的嘲笑从不与人红脸,对种种伤心话语表现出来的难得的平静,我的心在发酸。

    前年年底,按照她的嘱咐,年关之前要和女友赶到家里。我事先和女友讲好,娘一辈子在农村劳作,显老显丑,见了面多说宽心话。女友说:“谁没有老的一天,但娘一定不丑。”

    到家了,不知怎的,我们发现屋里空荡荡的,弟弟的眼睛红肿,精神不振。我一问才知道娘在三天前生了重病,住院了。弟说娘不想让我知道,要不会冲我和女友的喜。望着突然空寂和失去生气的屋子,我极力控制着自己的感情。弟又捧过一红布包给我,说是娘特意交代的,我打开一看,原来是两双精致的毛边布鞋,一大一小,显然一双是给我的,一双是给她未来媳妇的。看着看着,我和女友的眼泪如泉水般涌了出来。

    现在,我时时想起儿时老师说过的话:“你娘一定很漂亮吧?”

同类题5

阅读理解

    In ancient Egypt, the pharaoh(法老) treated the poor message runner like a prince when he arrived at the palace, if he brought good news. However, if the exhausted runner had the misfortune to bring the pharaoh unhappy news, his head was cut off.

    Shades of that spirit spread over today's conversations. Once a friend and I packed up some peanut butter and sandwiches for an outing. As we walked light-heartedly out the door, picnic basket in hand, a smiling neighbor looked up at the sky and said, ”Oh boy, bad day for a picnic. The weatherman says it's going to rain.”I wanted to strike him on the face with the peanut butter and sandwiches. Not for his stupid weather report, for his while!

    Several months ago I was racing to catch a bus. As I breathlessly put my handful of cash across the Greyhound counter, the sales agent said with a broad smile ,”Oh that bus left five minutes ago.” Dreams of head-cutting!

    It's not the news that makes someone angry. It's the unsympathetic attitude with which it's delivered. Everyone must give bad news from time to time, and winning professionals do it with the proper attitude. A doctor advising a patient that she needs an operation does it in a caring way. A boss informing an employee he didn't get the job takes on a sympathetic tone. Big winners know, when delivering any bad news, they should share the feeling of the receiver.

    Unfortunately, many people are not aware of this. When you're tired from a long flight, has a hotel clerk cheerfully said that your room isn't ready yet? When you had your heart set on the toast beef, has your waiter mainly told you that he just served the last piece? It makes you as traveler or diner want to land your fist right on their unsympathetic faces.

    Had my neighbor told me of the upcoming rainstorm with sympathy, I would have appreciated his warming .Had the Greyhound salesclerk sympathetically informed me that my bus had already left, I probably would have said, ”Oh, that's all right. I'll catch the next one.” Big winners, when they bear bad news ,deliver bombs with the emotion the bombarded(被轰炸的)person is sure to have.