如图所示，MN和PQ为两个光滑的电阻不计的水平金属导轨，变压器为_爱下问搜题

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问题多选题

如图所示，MN和PQ为两个光滑的电阻不计的水平金属导轨，变压器为理想变压器，今在水平导轨部分加一竖直向上的匀强磁场，则以下说法正确的是

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A．若ab棒匀速运动，则I_R≠0，I_L≠0，I_C=0

B．若ab棒匀速运动，则I_R≠0，I_L=0，I_C=0

C．若ab棒在某一中心位置两侧做往复运动，则I_R≠0，I_L≠0，I_C≠0

D．若ab棒做匀加速运动，I_R≠0，I_L≠0，I_C=0

答案

CD

填空题

（Ⅰ）有一包白色粉末，可能含有NaHSO₄、KHCO₃、Ba(NO₃)₂、CaCl₂、NaNO₃、MgSO₄中的一种或几种。

（1）取少量粉末投入水中，既有气体又有沉淀产生；

（2）过滤，取少量滤液，加入AgNO₃溶液，无沉淀产生；

（3）再取少量滤液，加入NaOH溶液，也无沉淀产生。

推断白色粉末中一定有_______，一定没有_______，不能肯定有没有的是________。

（Ⅱ）现有A、B、C、D、E五种盐溶液，分别由K⁺、NH₄⁺、Ag⁺、Ba²⁺、Al³⁺、Cl^-、Br^-、CO₃^2-、

SO₄^2-、NO₃^-中的阳离子与阴离子各一种组成（五种盐所含阴、阳离子各不相同）。

已知：①A+B→白↓；②A+C→白↓；③A+D→白↓；④B+C+H₂O→白↓+气体；⑤A的溶液呈中性；

⑥B的溶液中c（OH^-）>c（H⁺）；⑦C、D、E三种溶液的pH<7

根据以上事实，回答下列问题：

（1）写出化学式：C__________D__________E_____________

（2）写出④的离子方程式：______________________

完形填空

I was brought up by my grandparents for the first years of my life. We   36  in a very small community and all of my aunts and uncles lived   37_ . Everyone had a hand in taking care of my safety. Of course in those days   38  everyone in the community spoke the beautiful language of my childhood. When my grandfather spoke I would _ 39_ him carefully.
Then at age six my father   40  from the army. I was forbidden to speak that 41  ever again. My grandfather was   42  . He couldn’t speak English, so my grandmother would   43  for him whenever he spoke to me. With my mother and father we   44 from that small community. I was about to enter public school so I had to learn English. My grandfather   45  when I was eight and we returned to that small community for his funeral. He was   46  in the living room, as was the tradition. I went and stood by him and   47  no one was around I spoke to him in a whisper   48  that beautiful language of my childhood. That was the   49  time I spoke those words.
Almost fifty years later, _ 50 _ I had forgotten the beautiful language of my childhood, I had the opportunity to   51  a newly written paper of it. On my first look at it I recognized   52  . I must have looked it over several times in the following weeks. Then one day I read out loud a word from my past. I almost cried. I was   53 reading over other words. Words came   54  back to me after all these years. When receiving something from someone, you don’t take it from their hand, rather you let them lay it in your hand. For me it was   55  ---The beautiful language of my childhood was Michif. It was not only a language but also a way of life.

C．heartbroken

D．warm-blooded

A．carried out

A．long before

C．before long