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用Ba(OH)2溶液测定某种氮肥中(NH42SO4的质量分数(杂质溶于水,但不参加反应).实验如下:称取该氮肥20g加水完全溶解,向该溶液中不断滴入Ba(OH)2溶液,生成气体及沉淀质量与加入Ba(OH)2溶液的质量关系如下所示:

实验次序

1

2

3

滴入Ba(OH)2溶液的质量/g

20

40

60

生成气体的质量/g

0.85

m

2.55

试分析并计算:[已知:(NH42SO4+Ba(OH)2=BaSO4↓+2H2O+2NH3↑]

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                                                                                        How Important Is Fashion?

    Is looking fashionable more important than being comfortable? Many people seem to think so, judging by the things they wear. But fashion is not everything. It is more important to be a healthy and good person.

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    If the purpose of fashion is to make a person feel good, it does not make sense that he or she would go through so much discomfort to be fashionable. Fashion should not come first. People should prioritize(优先考虑)being healthy and positive. What people wear does not indicate anything about their personalities. Instead of going on strict diets and starving, why not eat some healthy foods and then exercise? By doing these things, you can keep a healthy lifestyle and truly grow as a person.