Objective To find better conditions and methods to improvethe accuracy and reliability of the measurement by evaluating andanalyzing the total molybdenum uncertainty in soil. Methods The contentof total molybdenum in soil was determined by inductively coupled plasmamass spectrometer with three acid digestion. Results The detection limitof the method was ${0.011}\mathrm{{mg}}/\mathrm{{kg}}$ , thecorrelation coefficient $\mathrm{R}$ of the calibration curve was 0.9999, the recovery was ${97.8}\%$ -105.6%, and the precision of themethod was 2.49%. The extended uncertainty of the method for thedetermination of total molybdenum content in soil was $\left({{0.660}\pm {0.03}}\right)\mathrm{{mg}}/\mathrm{{kg}}\left({\mathrm{K}=2}\right)$ . Conclusion By analyzing the main sources affectingthe uncertainty of measurement, the factors affecting the uncertainty ofthe whole process of determination, such as repeatability, curvefitting, standard solution, sample constant volume, sample weighing,glass measuring tools and sample digestion process were analyzed.Firstly, various conditions during the digestion process, such asdigestion temperature and digestion time, should be strictly controlledto reduce the sample loss. Secondly, microwave digestion, high pressuredigestion and other technologies can be used to optimize thepre-treatment mode to improve the accuracy and reliability of themeasurement results.

inductively coupled plasma mass spectrometer  /  soil  /  all molybdenum  /  uncertainty