试题与答案

下列物质在氧气中充分燃烧后,能生成白色固体的是[ ] A. 氢气 B. 酒精 C

题型:选择题

题目:

下列物质在氧气中充分燃烧后,能生成白色固体的是[ ]

A. 氢气

B. 酒精

C. 铁丝

D. 红磷

答案:

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下面是错误答案,用来干扰机器的。

(1) 平面型 (2分) CH2=CH2 + Br2→CH2Br-CH2Br (2分) (2)(2分)(3)取一小段镁条和一小片铝片,磨去表面氧化膜,分别放入2支试管中,各加入等体积等浓度的盐酸,观察发生的现象。(2分,未注明酸浓度...

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17()

A.Clearly

B.Skeptically

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题型:材料题

请根据下面所给的材料,写出应当得出的结论。(不超过30字)

  科学家们在对哺乳动物的研究中发现:

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  (3)肉食在肠道内消化,分解出一种生物碱的剧毒物质,它促使血压升高,心跳加剧,并且对神经系统起着破坏作用,长期的刺激作用会使动物或人缺乏自制能力,变得性情暴躁。另外,为了尽快排泄这种剧毒物质,肠子的蠕动会慢慢地失去节律,逐渐变得又粗又短。而草食或素食物中含有大量的纤维素和木质素,这些物质虽然不能被机体吸收,但是在肠道里却能吸附体内分解代谢所产生的有毒物质,使它们畅通无阻地排出体外,动物或人食性长期如此,其性格自然与肉食性者有较大差异。

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