重铬酸钾标准滴定制备液浓度的不确定度评定

Uncertainty Evaluation for Potassium Bichromate Standard Titrating Solution Content

依照国标JJF1059-1999《测量不确定度评定与表示》等规范的规定,对重铬酸钾标准滴定制备液浓度进行不确定度评定,以期找出影响制备该溶液浓度不确定度的主要因素,提高制备质量,并为下一步使用该溶液对样品进行检测做不确定度评定时提供必要的上一级不确定度信息。经评定,制备的C(1/6 K2Cr2O7)=0.05000 mol.L-1溶液浓度扩展不确定度为0.00007mol.L-1,K=2。不确定度评定结果表明,对本制备液浓度不确定度贡献最大的是溶液体积,其次是重铬酸钾基准物质的纯度,在制备时应加以重视。

Uncertainty of potassium bichromate standard titrating solution content was evaluated based on the government standard. The results showed that the uncertainty of 0.50000mol/L potassium bichromate solution was 0.00007mol/L,K=2, and it was showed that the large contribution to the uncertainty was solution volume, next was purity of potassium bichromate standard substance.