题干

下列关于碳及碳的化合物的说法错误的是(  )


A:石墨、金刚石、C60的物理性质不同,但都属于碳的不同单质

B:乙烯(X)的燃烧反应为X+3O22H2O+2CO2,则乙烯的分子式为C2H4

C:含碳的化合物中甲烷、乙醇属于有机物,CO、CO2则属于无机物

D:CO2能使紫色石蕊试剂变红,说明CO2显酸性

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D

同类题1

阅读下面的文字,完成下面小题。

端午的阳光

熊红久

    公元前278年的五月初五,被流放至泪罗江畔的屈原,得知秦国军队已攻破楚国郑都,顿时感到支撑生命的最后一点亮光熄灭了。

    当他把“举世皆浊我独清,众人皆醉我独醒”的诗句吟诵给江边i}x,父的时候,就已经决定,要将自己的清澈与江水的澄明合二为一了。我知道,这是屈子为保留个体纯净最无奈的选择,也是迄今为止,文化祭坛上最高尚的选择。

    最终,三间大夫坐在了泪罗江边,坐在了五月初五的阳光里,把最后的生路溺死水中。

    怀中石的沉重,恰如其心,所以屈原是抱着自己冰凉的心,走进激流之中的。而那些“长太息以掩涕兮,哀民生之多艰”“亦余心之所善兮,虽九死其扰未悔”的诗句,留在了岸上,留给了端午。一条江因为成了一个诗人心灵最后的归属地,而永远被世人铭记。一个普通的节日,因为收留了伟大诗人的高尚魂魄,而内涵充盈。

    端午,把缅怀和敬仰裹成了节日的粽心。

    节日的寿命当然要比人的寿命长久许多,所以,三间大夫把自己的傲骨托付给了这个日子。在结束自己生命肉体的同时,也放射出了精神的光芒。被江水灌洗的灵魂,忧如江面的粼粼波光,刺痛了后人的视线和思想。我知道,这种深入骨髓的隐痛,来自时间深处的行吟,一个背负着深重苦难,行走了两千多年的节日,其实是在为自己的存在寻找一个答案。

    所以,端午节带给我们的,应该是溯流而上的文化追源,恰如诗人余光中所说:“蓝.墨水的上游,是泪罗江。”

    以我们现在的视角来看,用一个诗人的限落,唤醒了一种文化的崛起,就像屈大夫生未能拯救楚国,却用死成就了《离骚》一样二忽然觉得,端午节其实更像是包裹粽子的苇叶了,它把所有的内容和精髓,密密细细地包藏起来,让我们极具耐心地一层层打开,最后领略到事物的真相。熟透之时,苇叶汲取了擂米的私质,擂米渗透着苇叶的清香,似如端午与屈子之间的浸染,节与人的统一。

    我对端午节的最初认知,完全来自于粽子:那时候的小学课本,还没有涉及到“楚辞”或者《离骚》的片言碎语,文化不高的母亲也无法给我们讲述端午节的由来,好在粽子并不因为我们的无知而改变所蕴含的味道,我总会把端午节和甜香私软的糯米联系起来。这使得整个贫乏的生活,还能透射出星星点点的光亮,就像枯枝间的芭蕾,渗漏出些许隐秘的春意。

    现在看来,那些夹杂在一年日历中为数不多的能激发我们饮食向往的节日,早已成为精神上抵档艰难生活的盾牌。从这个意义上说,我们应该为拥有这些值得回味的生活而向三间大夫叩谢。对童年而言,这是一个多么充满人情关怀的节日啊!那种甜腻的感觉,一直泛舟舌津。

    后来知道了屈原和楚怀王,知道了《国疡)和泪罗江,知道了每年这一天,人们蜂拥江岸,插艾篙、挂首蒲、吃粽子、竞龙舟,把一种悲情的怀念渲染成了欢悦的行为,热热闹闹,轰轰烈烈。

    历史会在很多场合拐出一道弯来,就像屈原投江时所选择的河泊潭一样—它是泪罗江注入洞庭湖口前的弯曲处。这种弯道,对河流而言,只是改变了水的流向;对三间大夫而言,却是以生命为笔,填充了历史的章节,引领了情感的走向。许多典故都停泊在河流的弯道,这些远航至此的细节,因为承载了有温度的夙愿,使得坚硬的历史柔软了许多。所以,更多的时候,是生命的结局让历史的叙述更具悲情。明白了这一点,再品尝粽子时,心情会沉重许多。

    事情往往是这样,在分享一种传统时,我们更多的时候只在关注它所带来的结果,而其中蕴含的真谛,却很少探究了。因为时空的距离,让来源变得愈加缥缈和混沌。好在历史给了我们最好的解决方式,它让时间淡化了一个国家的破碎的同时,却强化了一种品质的高贵。它让我们穿越两千三百年的距离,聆听到了一条河流古老的潮汐。这时候的端午,或许更像是一缕阳光,从泪罗江的源头流淌过来,映照着江边每一位过客的内心。

    我知道,有些品格是无法超越的,它更像一面古镜,端放在我们必经的路口,让人们从历史影像中,找到现实的映像。

(选自《人民日报》,有删改)

同类题5

阅读理解

    Scientists today are making greater effort to study ocean currents (洋流) . Most do it using satellites and other high-tech equipment. However, ocean expert Curtis Ebbesmeyer does it in a special way -- by studying movements of random floating garbage. A scientist with many years' experience, he started this type of research in the early 1990s when he heard about hundreds of athletic shoes washing up on the shores of the northwest coast of the United States. There were so many shoes that people were setting up swap meets to try and match left and right shoes to sell or wear.

    Ebbesmeyer found out in his researches that the shoes — about 60,000 in total — fell into the ocean in a shipping accident. He phoned the shoe company and asked if they wanted the shoes back. As expected, the company told him that they didn't. Ebbesmeyer realized this could be a great experiment. If he learned when and where the shoes went into the water and tracked where they landed, he could learn a lot about the patterns of ocean currents.

    The Pacific Northwest is one of the world's best areas for beachcombing(海滩搜寻) because winds and currents join here, and as a result, there is a group of serious beachcombers in the area. Ebbesmeyer got to know a lot of them and asked for their help in collecting information about where the shoes landed. In a year he collected reliable information on 1, 600 shoes. With this data, he and a colleague were able to test and improve a computer program designed to model ocean currents, and publish the findings of their study.

    As the result of his work, Ebbesmeyer has become known as the scientist to call with questions about any unusual objects found floating in the ocean. He has even started an association of beachcombers and ocean experts, with 500 subscribers from West Africa to New Zealand. They have recorded all lost objects ranging from potatoes to golf gloves.