题干

把干燥的蓝色石蕊试纸放在CO2气体中,石蕊试纸不变色.将CO2气体通入滴有石蕊指示剂的水中,溶液变红色.再将该溶液敞口加热一段时间,发现溶液的红色褪去,冷却到原温度后,再次通入CO2,溶液又变红色.上述实验现象不能说明的是(  )

A:CO2具有酸性

B:CO2能和水发生化学反应

C:CO2的水溶液具有酸性

D:加热能使CO2水溶液的酸性减弱

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答案(点此获取答案解析)

A

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阅读理解

    A culture's values can be mirrored by its humor. Humor has been evaluated by many great minds such as Thomas Hobbes, who, In"On Nature", disliked humor," Laughter is nothing else but sudden glory arising from sudden thought of feeling far better than others." He thought humor to be a negative quality of human narrow-mindedness.

    However, Mordechai Gordon, PhD of Education, insists," Humor allows us to view the world from an angle that is amusing rather than serious." I agree with Gordon. Learning to look at the world through humor is important.

    In the United States, every four years an election occurs. Without humor as a way to express their feelings, how would Americans be willing to support the election? Television shows like "The Daily Show" have become important parts of American culture. They are mothering the masses by unconsciously inputting politics into our mouths. They make politics fun.

    Of course, politics is only one type of humor. Social humor helps people through the twists and turns of the human condition. American pop culture promotes an unhealthy self image. On the topic of self-image, Hari Kondabolu stands out. He has a joke about the popular musical group "The Pussycat Dolls", describing their hit song "Don't Cha" as a negative representation of women. He points out an obvious offence in American culture.

    A study from Loyola University of Maryland has shown that humor is one determining factor for selecting a mating partner. Amongst other things, mates look for an outstanding funny bone in a potential partner.

    Of course, humor is not always used for good purposes. Humor can be linked to vulgarity(粗俗)and racism, but, like everything else, it has potential to unite human beings by allowing us to laugh at ourselves, our failures and our connection with one another.

    Though life may seem tough and depressing at times, all I have to do is look in the mirror at my increased wrinkles(皱纹)to know that there is a comedy out there that even Chaplin wasn't aware of.

    With that in mind, remember to laugh with humanity and sometimes at humanity.

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