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方法:1.将酚酞试剂溶于少许酒精中,加水稀释作成酚酞试液把滤纸剪成条状置于试液中,浸透取出晾干即制成酚酞试纸2.将酚酞试纸置入石灰水——Ca(OH)_2中,由于碱性反应酚酞试纸变成玫瑰红色(很鲜明)3.将潮润地红色酚酞试纸置入盛有萌发种子的玻璃瓶中(最好在前一日准备好,放在温暖而黑暗之处备用)不到两分钟,纸条受呼吸所产生的二氧化碳作用渐次转变成白色,课堂上在这一瓶内可以连作多次实验,效果仍然显著,学生可以充分观察明白。说明;1.酚酞试纸的碱性反应是红色;中性,酸性
Methods: 1. The phenolphthalein reagent was dissolved in a little alcohol, diluted with water to make phenolphthalein test solution The filter paper cut into strips placed in the test solution, soaking out to dry to make phenolphthalein test strip 2. The phenolphthalein test paper into lime water - -Ca (OH) _2 due to alkaline reaction Phenolphthalein test paper becomes rose red (very clear) 3. The moist red phenolphthalein test strips containing germination seeds in glass bottles (preferably the previous day ready, Placed in a warm and dark place for spare) less than two minutes, the paper by breathing the role of carbon dioxide gradually turned white, the bottle in the bottle can be repeated for many experiments, the effect is still significant, students can fully understand and understand . Description; 1 phenolphthalein test paper alkaline reaction is red; neutral, acidic