论文部分内容阅读
痕量氯离子的测定,通常采用比浊法,它要求较严格地控制温度、试剂加入的速度及搅拌等条件,而分析结果并非理想。为了避免采用比浊法,我们在常量容量法的基础上,探求一个快速、简便亦易掌握的微量容量法来测定痕量氯离子。试验证明:用刻度试管来控制溶液的体积,将微酸性的试液,用标准硝酸汞溶液滴定氯离子,二苯卡巴腙-溴酚蓝做混合指示剂,当溶液到达终点时,过剩的汞离子与指示剂形成紫色化合物,终点明显,即使1微克氯离子/毫升亦可测定,相对误差控制在3％以下。
Trace chloride ion determination, usually turbidimetric method, which requires more stringent control of temperature, the rate of addition of reagents and stirring and other conditions, and the analysis results are not ideal. In order to avoid the turbidimetric method, we seek a fast, simple and easy-to-grasp trace volume method for the determination of trace chloride based on the constant volume method. Tests show that: with a graduated test tube to control the volume of the solution, the slightly acidic test solution is titrated with a standard mercury nitrate solution of chloride, diphenylcarbazide-bromophenol blue as a mixed indicator, when the solution reaches the end point, excess mercury Ion and indicator form a purple compound, the end point is obvious, even if 1 microgram of chloride / ml can be measured, the relative error control in 3% or less.