几种常见滴定液长期稳定性考察

Study on the Stability of Several Common Titrants in a Long Period

通过长期考察乙二胺四醋酸二钠滴定液、亚硝酸钠滴定液、盐酸滴定液、硫代硫酸钠滴定液、氢氧化钠滴定液、硝酸银滴定液、硫酸滴定液、高氯酸滴定液的稳定性,为其有效期制定提供参考。每3个月考察滴定液的液性状是否改变和计算滴定液浓度差异相对平均偏差(RSD)是否大于0.1%来判定其有效期,每个滴定液考察3个批次。结果3~6个月内比较稳定的有乙二胺四醋酸二钠滴定液(0.05 mol/L)、亚硝酸钠滴定液(0.1 mol/L)、盐酸滴定液(0.1 mol/L)、硫代硫酸钠滴定液(0.1 mol/L)、氢氧化钠滴定液(0.1 mol/L)、硝酸银滴定液(0.1 mol/L),因此有效期建议定为3个月;硫酸滴定液(0.05 mol/L)、高氯酸滴定液在0~3个月内浓度差异比较大,建议有效期定在3个月内。

Provide data for making expiration date by study the stability of ethylene diamine tetraacetate disodium titrant,sodium nitrite titrant,hydrochloric acid titrant,sodium thiosulfate titrant,sodium hydroxide titrant,silver nitrate titrant,sulfuric acid titrant,perchloric acid titrant in a long period.Every 3 months,checked whether the liquid properties of the titration solution had changed and calculated whether the RSD of the concentration difference of the titration solution exceeds 0.1%to determine its validity period,examined three batches of each titrant.Found out that ethylene diamine tetraacetate disodium titrant(0.05 mol/L),sodium nitrite titrant(0.1 mol/L),hydrochloric acid titrant(0.1 mol/L),sodium thiosulfate titrant(0.1 mol/L),sodium hydroxide titrant(0.1 mol/L),silver nitrate titrant(0.1 mol/L)were stable in 3 to 6 months,the expiration dates could be 3 months.Sulfuric acid titrant(0.05 mol/L),perchloric acid titrant(0.1 mol/L)were not stable in 0 to 3 months,the expiration dates should be less than 3 months.