厨房中有许多化学物质，下列几种物质中属于纯净物的是（ ）
A．丹阳黄酒
B．加碘食盐
C．恒顺香醋
D．南山牌蒸馏水
A、丹阳黄酒中含有酒精和水，还有其他添加剂，属于混合物，故A错；
B、加碘食盐中含有氯化钠和碘酸钾等物质，属于混合物，故B错；
C、恒顺香醋中含有乙酸和水，属于混合物，故C错；
D、南山牌蒸馏水由水分子一种分子构成，属于纯净物，故D正确．
故选D．
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| Once upon a time there lived an old man in a nice cottage with a large garden. The old man was seen 1 his flowers all the time. They were so well-tended that every passer-by could not but 2 for a glance. One day a young man went by the garden. He gazed at the splendid garden, 3 in admiration at the beauty of these sceneries. Then, suddenly he 4 the old gardener was blind. 5 , the young man asked, "Why are you busy tending these flowers every day which you can't 6 in fact?" The old man smiled and answered that "I can tell you 7 reasons. First I was a 8 when I was young, and I really like this job. Second, although I can't see these flowers, yet I can 9 them. Third, I can smell sweetness of them. As to the last one, that's 10 ." "Me? But you don't know me," responded the young man 11 . "Yeah, it's 12 that I don't know you. But I know everyone knows flowers and would never 13 them down. I know the beauty of my garden will get many people into a good 14 . In the meantime, it also 15 a chance to me to have a word with you here and to enjoy the happiness these flowers have brought us." The old man's 16 astonished me. The blind man grows flowers and 17 them as a link of minds so as to make 18 enjoy the sunshine in spring. Isn't it one kind of happiness? I believe every flower has 19 with which they can see the kindness of the man's heart. The blind man grows flowers in his heart. Though 20 to see the beauty of blossoming, he surely can hear the voice of it, I suppose. | ||||
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cosωt
