问题
单项选择题 A1/A2型题
James染色法中5％甲醛液的作用是（）。
A.媒染
B.氧化
C.漂白
D.还原
E.镀银
答案
参考答案：D
解析：二氨银呈带正电荷的离子状态，能够被具有嗜银性质的网状纤维所吸收，经甲醛还原成金属银，因此甲醛液要新鲜配制，不能用陈旧性溶液，以防止银化合物不能还原成金属银。
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James染色法中5％甲醛液的作用是（）。
A.媒染
B.氧化
C.漂白
D.还原
E.镀银
参考答案：D
解析：二氨银呈带正电荷的离子状态，能够被具有嗜银性质的网状纤维所吸收，经甲醛还原成金属银，因此甲醛液要新鲜配制，不能用陈旧性溶液，以防止银化合物不能还原成金属银。
阅读短文，根据内容填写信息卡。 Nowadays, there are more and more TV talent shows. They are very popular all over China. These talent shows give everyone an opportunity to show off their talents. For some lucky people, these talent shows may make them famous, and can even make them rich. However, there are also many bad sides. First, some young people just imitate (模仿) their favorite stars. They may forget about their own styles. Second, young people spend too much time on such TV shows. They always dream of being a star. So they spend less time on their studies. In my opinion, these shows are social activities. Young people can take part in these activities to get social experience. But they should know that the chance of becoming famous is very small for most people. They should know that they should work hard at something more important, their school work. In short, you can do what you like, but you should know what is important and what is not. Information Card
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