论文部分内容阅读
碳酸钾、碳酸铵溶液都显碱性,可用酸碱滴定法测定其成份含量。碳酸铵与甲醛能定量反应生成碳酸,但不能直接用碱滴定。可先向试液中加一定量强酸,然后中和过量的酸,再加入甲醛溶液与其反应,用碱液滴定所生成的酸,求出碳酸铵的含量。方法已应用于本厂生产中。碳酸钾和碳酸铵以4:1～1:4不同重量比混合时,测定的结果是满意的。一试剂酚酞和百里酚蓝混合指示剂:1份0.1%百里酚蓝乙醇(1+1)溶液,3份0.1%酚酞乙醇(1+1)溶液。甲醛溶液:20%,甲醇允许量不超过1%,市售试剂甲醛一般含有约10%的甲醇,可用蒸馏法除去
Potassium carbonate, ammonium carbonate solution are alkaline, acid-base titration can be used to determine the content of its ingredients. Ammonium carbonate and formaldehyde can react quantitatively to form carbonic acid, but not directly titrated with alkali. Can be added to the test solution a certain amount of strong acid, and then excess acid, and then add formaldehyde solution and its reaction, with alkali titration generated acid, find out the content of ammonium carbonate. The method has been used in the factory production. The results of the determination were satisfactory when potassium carbonate and ammonium carbonate were mixed at different weight ratios of 4: 1 to 1: 4. A reagent mixture of phenolphthalein and thymol blue indicator: 1 part of 0.1% thymol blue ethanol (1 + 1) solution, 3 parts of 0.1% phenolphthalein ethanol (1 +1) solution. Formaldehyde solution: 20%, methanol tolerance does not exceed 1%, commercially available reagent formaldehyde generally contains about 10% methanol, can be removed by distillation