题干

苯乙烯是重要的化工原料。下列有关苯乙烯的说法错误的是

A:与液溴混合后加入铁粉可发生取代反应

B:能使酸性高锰酸钾溶液褪色

C:与氯化氢反应可以生成氯代苯乙烯

D:在催化剂存在下可以制得聚苯乙烯

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C

同类题1

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    Yesterday the police were joined by more than 20 volunteers in the continuing search for the two missing teenagers, Vicky Gray and Tom Hunter, and their guide, Gavin Jones. The police said that they had disappeared during an adventure tour of Cape York Peninsula.

    This was the second day of the search and the police were now very worried about the safety of the three missing people.

    The police said that the search had covered a wide area, but the rain forest was thick and their work was made harder by the recent rain. Later on Chief Inspector (警官) Roger Fleet said, “The travellers had a radio with them. If they had been in trouble, they would have called us.”

    The three travellers left Cooktown very early on Saturday morning in a Toyota car. They took a small dirt road that runs down to the Daintree River, a dangerous river full of crocodiles (鳄鱼). Chief Inspector Roger Fleet said the tourists wouldn't have got into trouble if they had stayed on the main road.

    A photo of Vicky and Tom was found by a policeman under the “Be Careful about crocodiles” sign near the river. Why was the photo left behind? This is just one of the unanswered questions. Other questions are: Why was the photo left behind? Why was the Toyota parked and locked at the edge of the rain forest? The police said that the travellers had left a map of the area behind. Why? Why had someone drawn a cross on the point where the car is? Is this a sign? What does it mean? If anyone can give information or has seen these three young people, contact the local police in Cooktown.

同类题2

阅读下文,完成后面小题。

三角梅

刘成章

       ①那年春天,我们陆续给小院栽了一些花木,其中包括一棵三角梅。我们知道三角梅可以开出很繁盛很灿烂的花,所以对它怀着极为美好的憧憬,特意把它栽在房屋山墙边极为显眼的地方,希望无论是谁来到我家门前,一眼就能看见。

       ②不料遇到了令人非常沮丧的事情。栽的时候,都一样认真,一样施足了底肥浇足了水,栽好之后,管理也没有偏三向四,可是别的花木都长得欢欢喜喜,到抽条时抽条,到开花时开花,一年下来,都长得很像个样子了,唯独那棵三角梅老是婴儿似的趴在那儿,停滞在那儿,好像完全忘了自己应该长长了。

       ③第二年,那棵三角梅仍然毫无变化。

       ④第三年,满院子的花木都长得青春勃发,高大喜人,那棵三角梅的叶片却比当初栽下时还少了好多,病恹恹的,一副要死不活的样子。我和老伴感伤地想,它总有一天会死去的。但自己亲手种下的,还曾怀有那样美好的憧憬,心中仍存那么一丝丝的期盼。

       ⑤去年是栽下它的第四个年头了。春天,当别的花木都在泛绿、发芽时,那三角梅依然毫无生机,一点要拥抱春天的意思都没有。我和老伴多次站在它面前皱眉,叹息,甚至责备。我们说,干脆把它拔了吧,省得它还占着一块地方,还要天天浪费几勺水。我的女儿和女婿,也是这样的观点。至此,全家的意见都一致了,欲除之而后快。

       ⑥然而,事情却出现了意想不到的变化。就在我们说这话后的不长时间,我们惊喜地看见,三角梅可怜兮兮的枝叶间,居然抽出了一枝表皮有着细致纹路的新条,而且长得很快,不久就长到二尺长了,接着又在那新条上旁逸斜出,生出了好几条侧枝。我们高兴极了。可为什么会突然发生这么大的变化呢?也许是我们要挖掉它的议论被它听懂了吧!如果是,对它来说,那可是个性命攸关的大事啊,于是它就拼命一搏,终于把生命的力量给搏出来了。好像每天太阳一出来,它就死盯着周围的花木,与它们比赛着成长。它身上透露出来的生机,非常生动地展现在蓝天之下,是那么醒目耐看。这时候与其他花木相比,它毫无逊色之处。它像沉默了好几年的毛毛虫,蓄满力量,开始向着花蝴蝶的方向蜕变了。

       ⑦又过了一个多月,我出门要干什么去,忽见山墙边露出一段红色的花枝,仔细一看,才发现竟然是三角梅开了一朵火红的花。它静静地趴靠在墙边,正好长了一人高。我急忙叫来老伴,让她也高兴高兴。老伴的眼中闪耀出多年来少见的美丽光彩。

       ⑧又是一个春天来临了,此时的三角梅已长成一棵枝茂花繁的大树,比房檐都高,它的红色花瓣就像红金子捶成的薄片,只要轻轻撞击就能发出动人的声音。太阳照射的时候,它的每朵花都泛溢着红色的光晕;风儿一吹,每朵花都像一只火红的蝴蝶张开了翅膀,扇动着,奋争着,仿佛急欲挣脱枝头,翩翩飞去。

       ⑨生命,在坚韧中真是蕴藏了无法言说的奥秘和潜能的!