以Ag+ 滴定Cl-的沉淀滴定计算分析为例 ,研究了电动势测定误差对滴定计算分析法的影响规律。理论推导与实验验证表明 :电动势测定误差对滴定计算分析法的影响小于直接电位法。电动势测定误差对滴定计算分析法测定结果C的影响与滴定分数α有关 ,在α =1处 ,这种影响为 0 ,α离 1越远 ,这种影响越大。这是因为C由D1 与D2 两部分组成 ,其中D1 与电动势无关 ,D2 与电动势有关。在α =1处 ,D2 对C的贡献为 0 ,α离 1越远 ,D2 对C的贡献越大。电动势测定的系统误差与偶然误差对单点滴定法均有影响 ,但在α =1附近 ,这种影响最小。电动势测定的系统误差是影响线性滴定法的主要因素 ,而偶然误差对线性滴定法的影响较小。电动势测定的偶然误差是影响双点滴定法的主要因素 ,而系统误差对双点滴定法没有影响 ;当电动势增量ΔE >- 0 .0 1 8V时 ,双点滴定法的误差一般大于单点滴定法 Taking the calculation of the precipitation titration of Cl- by Ag + titration as an example, the influence of the measurement error of electromotive force on the titration calculation and analysis was studied. The theoretical derivation and experimental verification show that the influence of the measurement error of the electromotive force on the titration calculation method is less than that of the direct potential method. The effect of electromotive force measurement error on the determination of C by titration calculation analysis is related to the titration fraction α, which is 0 at α = 1. This is because C consists of D1 and D2 two parts, of which D1 has nothing to do with the electromotive force, D2 and electromotive force. At α = 1, the contribution of D2 to C is 0, and the further α is from 1, the greater the contribution of D2 to C is. The systematic errors and occasional errors of electromotive force measurement all affect the single-point titration method, but the influence is the least in the vicinity of α = 1. The systematic error of the electromotive force measurement is the main factor that affects the linear titration method, and the accidental error has less influence on the linear titration method. The accidental error of electromotive force measurement is the main factor affecting the two-point titration method, and the systematic error has no effect on the two-point titration method. When the electromotive force increment ΔE> -0.018V, the error of the two-point titration method is generally larger than the single point titration method