题干

下列有关电解实验的说法不正确的是(   )

A:使用肼﹣空气碱性燃料电池作为电解精炼铜的电源,阴极的质量变化128 g,则肼﹣空气碱性燃料电池理论上消耗标准状况下空气的体积为112 L(假设空气中氧气的体积分数为20%)

B:若在电解水时加入少量硫酸钠,则电解水结束后溶液的pH将会保持不变

C:电解硫酸铜溶液一小段时间后,为了使电解质溶液复原,可以加入适量的Cu(OH)2

D:电解硫酸铜溶液产生氧气1.12 L(标准状况)时,转移电子0.2 mol

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C

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    People can't see you when you're speaking on the phone,but they can hear you.So,the way you speak is especially important.In fact,researchers have calculated that 80% of communication over the phone is through your tone of voice; and only 20% is from the words you use.Here are our top tips on how to speak over the phone.

⒈Facial Expressions

    Your facial expression can influence your voice.For example,if you smile,your voice will sound warm and friendly,just the opposite,if you have an angry look on your face,it can make you sound unpleasant.

⒉Volume

    If you speak too loudly,you could sound angry.And if you speak too softly,it'll be difficult to hear you.So,speak loudly enough to be heard clearly,but not so loud that you're shouting.

⒊Pace

    The pace of your voice is how quickly you speak.And this can show how you feel.For example,an angry person might speak faster than normal.Or a downhearted person might speak very slowly.Try speaking a little more slowly than normal.This will make you sound confident,and it'll make it easier for the other person to understand you.

⒋Gestures

    Gesturing can influence the tone of your voice.When you gesture,you bring more air into the lungs,which can make your voice sound warmer.Gestures are also useful to help you stress the right words or even find the words you need.The best thing about gesturing during a phone call is that no one can see what you're doing,so you can gesture as wildly as you like!

⒌Movement

    If you're feeling nervous,stand up and move around.It will reduce the nervousness in your body and help your voice to sound more confident.

⒍Pauses (停顿)

    Using pauses every now and then can help you to slow down.This will make you sound more confident and in control.Also,if you pause after giving some new information,it'll give the other person time to understand it.At the same time,listen to how the other person uses pauses.They could tell you something about the speaker's feeling.For example,when a speaker is really angry,he might use pauses and says,"I…am…so…angry…"