THE ANALYTICAL CHEMISTRY OF THORIUM 1. HOMOGENEOUS PRECIPITATION OF THORIUM SELENITE AND VOLUMETRIC DETERMINATION OF THORIUM

【摘要】 <正>By the hydrolysis of acetamide and slow neutralization of acid from。nitric acid solution, thorium selenite can be obtained in crystalline form. Theprecipitatethiosulfatecan be dissolvedin hydrochloric acid and titrated with sodiumsolution. This methodis simple and accurate; absolute error isgenerally lessthan 0.1 mg for 50 mg of Th02 or less.Relative error is notmore than 0.3% for 1’7.5 to 50mg of Th02.Smallthe weight of thoria,amounts of rare earths clonot interfere. Up to ten-foldrare earth oxides can betolerated, provided that the pH value is carefully controlled.更多还原

【Abstract】 By the hydrolysis of acetamide and slow neutralization of acid from a nitric acid solution, thorium selenite can be obtained in crystalline form. The precipitate can be dissolved in hydrochloric acid and titrated with sodium thiosulfate solution. This method is simple and accurate; absolute error is generally less than 0.1mg for 50mg of ThO₂ or less. Relative error is not more than 0.3% for 17.5 to 50 mg of ThO₂. Small amounts of rare earths do not interfere. Up to ten-fold the weight of thoria, rare earth oxides can be tolerated, provided that the pH value is carefully controlled.更多还原