Objective To evaluate the uncertainty of determination of free alkalinity in edible betelnut by potentiometric titration. Methods A mathematical model for affecting factors of the results of free alkalinity in edible betelnut was established, and the uncertainty evaluation of free alkalinity in edible betelnut by potentiometric titration was estimated. Results The results showed that the combined standard uncertainty was 0.065 mg/g and the expanded uncertainty was 0.13 mg/g when the free alkalinity was 6.5 mg/g in the edible betelnut sample. Conclusion The main source of the standard method for determination of free alkalinity in edible betelnut by DB43/132-2004 Edible betelnut is the uncertainty of the volume of hydrochloric acid standard titrition solution, so we should strictly control the titration end in the experimental process so as to ensure accurate and reliable results.
标题：电位滴定法测定槟榔中游离碱度的不确定度评定
英文标题：Uncertainty evaluation for determination of free alkalinity in edible betelnut by potentiometric titration
