题干

下列有关油脂的叙述错误的是

A:植物油能使溴水褪色

B:皂化反应是指油脂在碱性条件下的水解过程

C:硬水使肥皂的去污能力减弱是因为发生了沉淀反应

D:油脂的水解反应称皂化反应

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D

同类题3

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    My students often tell me they don't have “enough time” to do all their schoolwork. My reply is often brief—You have as much time as the president. I usually carry on a bit about there being 24 hours in the day for everyone, and suggest that “not enough time” is not an acceptable explanation of not getting something done.

    Once in graduate school, I tried to excuse myself to one of my professors by saying that I was working hard. His answer to me was, “That's irrelevant. What's important is the quality of your work.” Since then I have had time to think about the “hard worker” dodge (伎俩), and I have come to some conclusions — all relevant to the issue of how much time we have.

    If you analyze(分析) the matter, you can identify(确定) two parts of the problem: There is, of course, the matter of “time”, which we can think of as fixed. Then there is the problem of “work” during that time. But, as my professor suggested, it's not how hard one works but the quality of the product that is important.

    That led me to a new idea: the quality of the work. That concept is perhaps best explained by a sign I once saw on the wall in someone's office---Don't work harder but work smarter. There's a lot of sense in that idea.

    If you can't get more time, and few of us can, the only solution(解决方法) is to improve the quality of the work. That means thinking of ways to get more out of the same time than we might otherwise get. That should lead us to an analysis of our work habits. Since “work” for students usually means “homework”, the expression “work habits” should be read as “study habits”.

    Then, as a smart student, you will seek to improve those skills that you use in study, chiefly reading and writing. If you learn to read better and write better, there are big benefits that pay off in all your studies.