“绿色化学”是当今社会提出的一个新概念。在“绿色化学工艺”中，理想状态是反应中原子全部转化为欲制得的产物，即原子的利用率为100%。下列反应符合绿色化学这一特点的是
A．工业冶铁
B．用生石灰制熟石灰
C．实验室制二氧化碳
D．实验室用高锰酸钾制氧气
答案：B
A、工业冶铁，反应后生成铁与二氧化碳，有两种产物，并没有达到原料物质中的所有原子完全利用，全部转入期望产物，故A错误；
B、反应后只有熟石灰一种产物，并没有达到原料物质中的所有原子完全利用，全部转入期望产物，故B正确；
C、实验室制取二氧化碳，反应后生成氯化钙、水和二氧化碳，反应后有三种产物，原料物质完全被利用，故C错误；
D、实验室利用双氧水、氯酸钾或高锰酸钾制取氧气，发生的都是分解反应，反应后有两种或三种产物，并没有达到原料物质中的所有原子完全利用，全部转入期望产物，故D错误．
故选B．
In a nice house there lived an old man. Behind the house there was a big garden. He planted many plants there. He took care of his 41 all the time, watering and fertilizing (施肥) them. One day a young man went by the 42 . He looked at the beautiful flowers, imagining how happy he could be 43 he lived in such a beautiful place. Then, suddenly he found the old gardener was 44 . He was very surprised about this and asked, “You can’t see these flowers. 45 are you busy taking care of them every day?” The old man smiled and said, “I can tell you four 46 . First, I was a gardener when I was young, and I really like this job. Second, 47 I can’t see these flowers, I can touch them. 48 , I can smell the sweetness of them. As to the last one, that’s 49 .” “Me? But you don’t know me,” said the young man. “Yeah, it’s 50 that I don’t know you. But I know that flowers are angels that everybody 51 . We enjoy the happiness these flowers have brought us.” The blind man’s work opened our eyes and 52 our heart, which also made his life 53 . It was just like Beethoven, who became deaf in his later life and wrote many great musical words. Beethoven himself couldn’t 54 his wonderful music, but his music has 55 millions of people to face their difficulties bravely. Isn’t it one kind of happiness?
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