题干

蔬菜、水果中大多含有维生素C(C6H8O6).下列关于维生素c的说法错误的是(  )

A:维生素C属于化合物

B:维生素C中碳元素的质量分数最大

C:维生素C由碳、氢、氧三种元素组成

D:1个维生素C分子由6个碳原子、8个氢原子和6个氧原子构成

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答案(点此获取答案解析)

B

同类题1

阅读理解

    If you want to become a better reader, what should you know about speed of reading?

    Some people read very rapidly(快速地),while others read very slowly. But which one is better?

    The rapid reader may be a good reader when he reads a storybook for fun. But he may not be able to slow down enough to read directions carefully. He may read so rapidly that he does not take time to understand fully the ideas and information which are important to remember.

    The slow reader may be a good reader when he reads directions for making something. But he may spend too much time in reading a simple story which is meant to be enjoyed but is not important enough to be remembered.

    So, you see, either a rapid reader or a slow reader is not really a good one. If you wish to become a better reader, here are four important things to remember about speed of reading.

    1  Knowing why you are reading will often help you to know whether to read rapidly or slowly.

    2  Some things should be read slowly throughout. Examples are directions for making or doing something, science and history books, and Maths problems. You must read such things slowly or remember each important step and understand each important idea.

    3  Some things should be read rapidly throughout. Examples are simple stories for enjoyment, letters from friends and bits of news from hometown papers.

    4  In some of your reading, you must change your speed from fast to slow and slow to fast, as you go along. You will need to read certain pages rapidly and then slow down and do more careful reading when you come to important ideas.

同类题3

阅读下面的文言文,完成以下小题。

    成遵,南阳穰县人也。幼敏悟,读书日记数千百言。家贫,勤苦不废学问。二十能文章。时郡中先辈无治进士业者,遵欲为,以不合程式为患。会杨惠初登第,来尹穰,遵乃书所作数十篇见之,惠抚卷大喜。至京师,受业于夏镇,遂入为国子生。元统改元,中进士第,授翰林国史院编修官。至正改元,擢太常博士。寻拜监察御史。扈从至上京,上封事,言天子宜慎起居,节嗜欲,以保养圣躬,圣躬安则宗社安矣。言甚迫切,帝改容称善。又言台察四事,帝皆喜纳之。是岁,言事并举劾凡七十余事,皆指讦时弊,执政者恶之。三年,自刑部员外郎出为陕西行省员外郎。

    五年,丁母忧。十年,迁中书右司郎中。时刑部狱按久而不决者积数百,遵与其僚分阅之,共议其轻重,各当其罪。未几,无遗事。时有令输粟补官,有匿其奸罪而入粟得七品杂流者,为怨家所告。有司议输粟例无有过不与之文遵曰卖官鬻爵已非盛典况又卖官与奸淫之人其将何以为治必夺其敕还其粟著为令乃可省臣从之。十四年,调武昌路总管。会省臣出师,遵摄省事,于是省中府中,惟遵一人。乃远斥候,塞城门,籍民为兵,得五千余人,设万夫长四,配守四门,所以为防御之备甚至,号令严肃,赏罚明当。贼船往来江中,终不敢近岸,城赖以安。

十七年,升中书左丞。是时,太平在相位,以事忤皇太子,皇太子深衔之,以为遵及参知政事赵中,皆太平党也。十九年,用事者承望风旨,嗾邓子初等诬遵与参政赵中等六人皆受赃,皇太子命御史台等官杂问之,锻炼使成狱,遵等竟皆杖死,中外冤之。二十四年,御史台臣辩明遵等皆诬枉,诏复给还其所授宣敕。

                                      (节选自《元史·成遵传》,有删改)