题干

将镁片、铝片平行插入到一定浓度的NaOH溶液中,用导线连接成闭合回路,如图所示,该装置在工作时,下列叙述正确的是(   )

A:镁比铝活泼,镁失去电子被氧化成Mg2+

B:铝是电池负极,开始工作时溶液中会立即有白色沉淀生成

C:该装置的内、外电路中,均是电子的定向移动形成电流

D:该装置开始工作时,铝片表面的氧化膜不必处理

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D

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    “I don't feel right about this,” I said to one of my cousins in a low voice. She nodded in 1 . Not wanting to be the first to touch the food, I waited for one of the older adults to start.

    Thanksgiving usually meant 2  and full stomachs, however, this year was 3. My family sat around the dinner table 4 at our feast. Everyone had a full plate, everyone except for Grandma. The treatment for throat cancer would 5  one of her great pleasures, eating. This was the first 6of many food-focused 7  to come. I could not imagine what it would be like to never taste food again. My cousin Molly broke the 8 with a raise of her glass, “To Nat.” We all followed her lead. “Your 9 and strength encourage us all,” she continued. Grandma smiled, holding back her tears with great 10 . “Thank you. Please, please eat.” And with that, we all began to eat. Conversation broke 11around the room while Grandma laughed and talked with us all. Cancer would take away her ability to eat, but not the gift of being the best hostess. The evening went on as 12 Thanksgivings do. By the time the night was over, I felt 13 to my family than ever before. I learned that we gather together on holidays not to eat rich feast, but to 14 and share with one another. We 15 my Grandmother's courage, but we all learned a lesson in grace. In the years following, my Grandma 16 to create meals for family events. She told me once with a laugh, “I may not be able to eat, but I can 17 taste things.” With a 18 heart, Grandma prepared what she could not have for the only purpose of making us 19 . She inspired me to learn to cook and helped me find the 20 to make everything come together: love.