论文部分内容阅读
本法使用两种浓度的标准溶液(第一标液与第二标液浓度相差10倍)进行测定。由计算式可直接得出测定结果,从而简化了作标准曲线查表等实验步骤。 1.计算公式的推导设氟标准溶液的浓度为C_2和10C_1,欲测试样氟的浓度C_x(介于两标准溶液浓度之间)。Ec_1、Ex、E_(10)c_1分别为测得的电位值。则有: Ec_1=E_0+Slogf_1C_1 Ex=E_0+Slogf_2Cx E_(10)c_1=E_0+Slogf_310C_1 当溶液离子强度固定时,其活度系数 f_1=f_2=f_3 故 Ec_1=E_0′+SlogC_1 Ex=E_0′+SlogCx E_(10)c_1=E_0′+Slog10C_1 Ec_1-Ex=SlogC_1/C_x……(1)
This method uses two concentrations of standard solution (the first standard solution and the second standard solution concentration difference of 10 times) were measured. The formula can be directly derived from the measurement results, thus simplifying the standard curve table and other experimental steps. 1. Derivation of the calculation formula Let the fluorine standard solution concentration of C_2 and 10C_1, to be tested sample fluorine concentration C_x (between two standard solution concentrations). Ec_1, Ex, E_ (10) c_1 are the measured potential values respectively. (10) c_1 = E_0 + Slogf_310C_1 When the ionic strength of the solution is fixed, its activity coefficient is f_1 = f_2 = f_3 so Ec_1 = E_0 ’+ SlogC_1 Ex = E_0’ + SlogCx E_ (10) c_1 = E_0 ’+ Slog10C_1 Ec_1-Ex = SlogC_1 / C_x (1)