题干

将一块银白色的金属钠放在空气中会发生一系列变化:表面变暗→“出汗”→白色粉末。下列有关叙述中不正确的是(    )

A:表面迅速变暗是因为钠与空气中的氧气反应生成氧化钠

B:“出汗”是因为生成的氢氧化钠吸收空气中的水蒸气在表面形成了溶液

C:最后的白色粉末是碳酸钠

D:该过程的所有化学反应均为氧化还原反应

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D

同类题4

    I've loved my mother's desk since I was just tall enough to see above the top of it as mother sat doing letters. Standing by her chair, looking at the ink bottle, pens, and white paper, I decided that the act of writing must be the most wonderful thing in the world.
    Years later, during her final illness, mother kept different things for my sister and brother. “But the desk,” she'd said again, “it's for Elizabeth.”
    I never saw her angry, never saw her cry. I knew she loved me; she showed it in action. But as a young girl, I wanted heart-to-heart talks between mother and daughter
    They never happened. And a gulf opened between us. I was “too emotional(易动感情的)”. But she lived “on the surface”.
    As years passed I had my own family. I loved my mother and thanked her for our happy family. I wrote to her in careful words and asked her to let me know in any way she chose that she did forgive me.
    I posted the letter and waited for her answer. None came.
    My hope turned to disappointment, then little interest and, finally, peace—it seemed that nothing happened. I couldn't be sure that the letter had even got to mother. I only knew that I had written it, and I could stop trying to make her into someone she was not.
    Now the present of her desk told, as she'd never been able to, that she was pleased that writing was my chosen work. I cleaned the desk carefully and found some papers inside-- a photo of my father and a one-page letter, folded(折叠) and refolded many times.
    Give me an answer, my letter asks, in any way you choose. Mother, you always chose the act that speaks louder than words.