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一、问题提出人教版高中化学选修4教材第二章第二节有如下“科学探究”:“已知4H~++4I~-+O_2=2I_2+2H_2O,现有1 mol/L KI溶液、0.1 mol/L H_2SO_4溶液和淀粉溶液,请探究溶液出现蓝色的时间与温度的关系。”在一次学生实验的准备过程中,虽然我们查阅资料得知碘与淀粉的显色反应不宜在较高温度下进行,故实验中均将温度控制在了50℃以下,但教师们因药品用量和加入顺序不同出
First, the problem proposed PEP high school chemistry elective 4 textbook Chapter II, Section II has the following “scientific inquiry”: “known 4H ~ + 4I ~ - + O_2 = 2I_2 + 2H_2O, the existing 1 mol / L KI solution, 0.1 mol / L H 2 SO 4 solution and starch solution, please explore the relationship between the solution blue time and temperature. ”In a student experiment preparation process, although we refer to the information that iodine and starch color The reaction should not be carried out at higher temperatures, so the experiment will be controlled at a temperature below 50 ℃, but the teachers because of the amount of drugs and join the order of different