Final report on key comparison CCQM-K96: Determination of amount content of dichromate

Abstract

The key comparison CCQM-K96 was organized jointly by the inorganic and electrochemistry working groups of CCQM to test the abilities of the metrology institutes to measure the amount content of dichromate. Slovak Institute of Metrology with help of KRISS acted as the coordinating laboratories. Eight NMIs took part in the comparison. All participants used high accuracy constant current coulometry. Good agreement of the results was observed.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Development of a coulometry system at the Korea Research Institute of Standards and Science and evaluation of the measurement uncertainty originating from the system

“…The performance of the first coulometry system was verified by the CCQM KC results [5][6][7][8][9][10]12] reported by the KRISS, as presented in table 9. The absolute values of the degrees of equivalences (d i ) divided by the expanded uncertainty of the d i for all results are less than 1, which indicates that all of the results obtained using the first coulometry system are consistent with the KC reference values within the associated expanded uncertainties.…”

“…The Electrochemical Analysis Working Group within the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) first introduced this method in the CCQM-P7 international comparison to measure the amount content of various materials, such as K 2 Cr 2 O 7 , KCl, and NaCl [4]. Since then, national measurement institutes (NMIs) around the world have made efforts to establish national measurement standards for the amount contents of high-purity primary standards used in acid-base, redox, and precipitation titrations using this method, and numerous CCQM key comparisons (KCs) have been conducted to demonstrate the international equivalence between the established national measurement standards [5][6][7][8][9][10][11][12][13]. As part of these efforts, the Korea Research Institute of Standards and Science (KRISS) built its first coulometry system in 2000 and has recently constructed a second coulometry system to support ongoing research in the field of coulometry.…”

Application of direct and indirect methods for determining the mass fraction of the main component in flotation potassium chloride

“…QM-S11, CCQM-P149, CCQM-P107.1. Результаты международных сличений по измерению основного компонента в чистых веществах (в диапазоне от 99,0 % до 100,0 %) отражены в [35][36][37][38], по измерению элементов примесей (в диапазоне от 10 -8 % до 10 -2 %) в [28,39].…”

Metrological evaluation of the certification of primary reference materials characterized by high-precision constant-current coulometry for the reliability of the titration analyses

“…The Electrochemistry Laboratory from Inmetro has participated in several KCs. Table 5 presents the results obtained by Inmetro in the KCs for using coulometry to determine the purity of K 2 Cr 2 O 7 , KCl, and KHP named CCQM-K96 [41], CCQM-K48 [42], and CCQM-K34.2 [43], respectively, as well as the key comparison reference values (KCRVs) and the degrees of equivalence (DoEs), as determined by the results from…”