题干

下列实验方法或实验叙述正确的是(  )


A:将pH试纸直接放入某溶液中,测定该溶液的pH

B:用澄清石灰水鉴别NaHCO3和Na2CO3

C:过滤操作时,漏斗下部的尖嘴要紧靠烧杯的内壁

D:从碘水提取碘可用乙醇作萃取剂

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答案(点此获取答案解析)

C

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    My mom takes pride in the fact that I was talking in three and four word sentences before I was ten months old. Some say it's a gift while others simply think I talk too much.

    As my thirties came to a close, I found myself reflecting on my life. I'm very happy and have no significant regrets. However, when I looked back on those times of difficulty, I saw a clear common denominator(特征); I didn't seem to know when to stop talking. Whether it was hurting someone's feelings, or having carelessly told a secret, the incident could have been avoided had I closed my mouth sooner. So I decided to practice the power of quiet.

    To take this step, I needed to understand how people could sit comfortably in a group and not talk. Why does my husband feel completely content to say nothing in a conversation? He's highly intelligent and has wonderful opinions but he'll sit quietly and just listen. Even when he's asked a pointed question, he'll answer with few words while still communicating effectively. What a talent!

    Can you imagine being happy just listening? In surveying those I know who talk less than I do, I got two answers—they either didn't feel confident enough to speak up, or they just didn't feel the need to participate in the conversation. Of course there were other reasons for not talking, but these were the two most popular answers.

    The first one didn't work for me. I'm just fine letting people know what I think about them, and hopefully it will make the conversation much more interesting. The second one didn't work either. I do feel the need to participate. I feel it physically like an electrical pulse through my body; sometimes it's so strong that it causes me to behave badly in the form of interrupting or speaking in an unusually loud voice. I had to look further.

    An interesting thing happened on this journey to the power of quiet. During my weekly yoga class, it came to me like an answer so clear that the words rang in my head like soft, heavenly bells.

    I talked too much so people would know I cared about them. It was my way of taking care of those I love. I decided before my fortieth birthday, that from that day forward, those around me would know I loved them, and cared what they thought and felt, but I was going to practice the power of quiet.

    As my forty-second birthday approaches, I can say that deciding to talk less has been more about focusing on quality rather than quantity. I've found that listening more shows those who I care about that I really do care how they feel. Now when I break in, it means more to them. Oh, sure, I still have my short periods of talking too much, but for the most part this has been one resolution that I can call a success.