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,再次通人CO2,溶液又变红色.上述实验现象不能说明的是(  )

A:CO2能和水发生化学反应

B:CO2的水溶液具有酸性

C:以加热能使CO2水溶液的酸性减弱

D:CO2具有酸性

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D

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Make Up Your Mind to Succeed

    Kind-hearted parents have unknowingly left their children defenseless against failure. The generation born between 1980 and 2001 grew up playing sports where scores and performance were played down because “everyone's a winner.” And their report cards sounded more positive  than ever before. As a result, Stanford University professor Carol Dweck, PhD, calls them “the overpraised generation.”

    Dweck has been studying how people deal with failure for 40 years. Her research has led her to find out two clearly different mind-sets that have a great effect on how we react to it. Here's how they work:

    A fixed mind-set is grounded in the belief that talent is genetic – you're a born artist, point guard, or numbers person. The fixed mind-set believes it's sure to succeed without much effort and regards failure as personal shame. When things get difficult, it's quick to blame, lie, and even stay away from future difficulties.

    On the other hand, a growth mind-set believes that no talent is entirely heaven-sent and that effort and learning make everything possible. Because the ego (自尊) isn't on the line as much, the growth mind-set sees failure as a chance rather than shame. When faced with a difficulty, it's quick to rethink, change and try again. In fact, it enjoys this experience.

    We are all born with growth mind-sets. (Otherwise, we wouldn't be able to live in the world.) But parents, teachers, and instructors often push us into fixed mind-sets by encouraging certain actions and misdirecting praise. Dweck's book, Mind-set: The New Psychology of Success, and online instructional program explain this in depth. But she says there are many little things you can start doing today to make sure that your children, grandchildren and even you are never defeated by failure.