题干

电渗析法是一种利用离子交换膜进行海水淡化的方法,其原理如下图所示.已知海水中含Na+、Cl﹣、Ca2+、Mg2+、SO 42− 等离子,电极为惰性电极.下列叙述中正确的是(    )

A:A膜是阳离子交换膜

B:通电后,海水中阴离子往b电极处运动

C:通电后,b电极上产生无色气体,溶液中出现白色沉淀

D:通电后,a电极的电极反应式为4OH﹣﹣4e﹣═O2↑+2H2O

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C

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    The world always makes way for the dreamer

    When I was twelve years old, my father took me to see Zig Zigler. I remember sitting in that dark hall listening to Mr. Zigler1everyone's spirits up to the ceiling. I 2there feeling like l could do anything. When we got to the car, I turned to my father and said, "Dad, I want to3 people feel like that." My father asked me 4 I meant. "I want to be a motivational speaker just like Mr. Zigler." I replied. A(An)5  was born.

    Recently, I began seeking my dream of motivating others. 6  a four-year relationship with Fortune 100 Company 7as a sales-trainer and ending as a regional(地区的) sales manager, I left the company at the height of my8. Many people were9that I would leave after earning a six-figure income. And they wondered10I would risk everything for a dream.

    I made my 11 to start my own company and leave my worryingless position after12a regional sales meeting. The vice-president of our company made a13 that changed my life. He asked us, "If a god would offer you three wishes, what would they be?" After giving us a(an)14 to write down the three wishes, he then asked us, "Why do you need a 15 ?" I would never forget the power I felt at that moment. I realize that 16 I had accomplished in the past had prepared me for this moment. I was ready and didn't need a god's help to become a motivational speaker. A motivational speaker was17 .

    Having made that decision, I was immediately18 . One week after I gave notice, my husband was laid off from his job, and now we had no 19. But I held fast to my dream. The wonder really began to happen. In a short time my husband found a better job. And I was able to book several 20 engagements with new customers. I discovered the incredible power of dreams.