题干

实验室常用锌和稀硫酸制取氢气,下列操作错误的是(   )

A: 稀释浓硫酸

B: 加入锌粒  

C: 产生氢气

D: 收集氢气

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D

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    Have you ever noticed what happens to an idea once you express it? Just talking about it or writing it down causes you to make it clear in your own mind. How can you use this to increase your brain power? Start writing.

    By putting thoughts into words, you are telling yourself the logic(逻辑)behind what you think, feel, or only partly understand. Often, explaining a thought is the process of understanding. In other words, you increase your brain power by exercising your “explain power.”

    Try this experiment. Explain how you'll increase your brain power, even if you have no idea right now. Just start with anything, and create an explanation. For example, start with “I'll learn chess,” or “I'll read an article on the mind every week.” Explain how that will help. You'll be surprised how often this becomes a workable plan, and if you actually do this, you'll have a better understanding of your brain from now.

    Another benefit of writing is that it helps you remember. Many, if not most, highly productive people are always taking notes. You can try keeping it all in your head, but if you keep a journal of your ideas the next time you're working on a big project, you'll probably have more success.

    Want to understand a topic? Write a book about it. That's an extreme example, but if you are learning something new, write a letter to a friend about it, and you will understand it better. Want to invent something? Write an explanation of the problem, why you want to solve it, and why it is worth solving, and you're half-way there.

    Writers don't always write because they clearly understand something beforehand. Often, they write about something because they want to understand it. You can do the same. Writing will help bring you to an understanding. Give it a try.