CCQM-K34, CCQM-K34.1 and CCQM-K34.2
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
Degrees of equivalence: Di = (xi - xR) and expanded uncertainty Ui (k = 2), both expressed in mol/kg
Degrees of equivalence: (Di / xR) and expanded uncertainty (Ui / xR) (k = 2), both expressed in %
Red diamonds: participants in CCQM-K34
Green triangle: participant in CCQM-K34.1
Blue circles: participants in CCQM-K34.2
CCQM-K34, CCQM-K34.1 and CCQM-K34.2
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
| Lab i | Di | Ui |
| / (mol/kg) | / (mol/kg) | |
| NMIJ | -0.0008 | 0.0015 |
| KRISS | -0.00012 | 0.00046 |
| SMU | -0.00001 | 0.00046 |
| NIM | 0.00001 | 0.00064 |
| NIST | 0.00028 | 0.00046 |
| UNIIM | 0.0019 | 0.0016 |
| BAM* | 0.0001 | 0.00058 |
| INMETRO** | -0.0004 | 0.00057 |
| UNIIM** | -0.0003 | 0.00082 |
* participant in CCQM-K34.1
** participants in CCQM-K34.2
Degrees of equivalence with respect to the key comparison reference value, expressed in relative terms: (Di / xR) and (Ui / xR) :
* participant in CCQM-K34.1
** participants in CCQM-K34.2
Sets of absolute and relative degrees of equivalence are available in Summary Results (PDF file, presented under A4 printable format).
| Metrology area, Sub-field | Chemistry and Biology, Electrochemistry |
| Description | Assay of potassium hydrogen phthalate |
| Time of measurements | 2004 |
| Status | Approved for equivalence |
| Final Reports of the comparisons | |
| Measurand | Amount content, expressed in mol/kg |
| Transfer device | Dedicated samples |
| Comparison type | Key Comparison |
| Consultative Committee | CCQM (Consultative Committee for Amount of Substance) |
| Conducted by | CCQM (Consultative Committee for Amount of Substance) |
| Comments | CCQM-K34 was decided jointly by the Electrochemical Analysis and the Inorganic Analysis Working Groups of the CCQM. CCQM-K34.1 and CCQM-K34.2 results are linked to those of CCQM-K34 CCQM-K34 results published on 27 March 2006 Amount content of weak acid in potassium hydrogen phthalate |
| Pilot institute |
SMU
Slovensky Metrologicky Ustav Slovakia |
| Contact person | Michal Mariassy +421 2 602 94 522 |
| Pilot laboratory | |
|---|---|
| SMU |
Slovensky Metrologicky Ustav, Slovakia, EURAMET |
| BAM |
Bundesanstalt für Materialforschung und -prüfung, Germany, EURAMET |
| KRISS |
Korea Research Institute of Standards and Science, Korea, Republic of, APMP |
| NIST |
National Institute of Standards and Technology, United States, SIM |
| NMIJ AIST |
National Metrology Institute of Japan, Japan, APMP |
| NRCCRM |
National Research Centre for Certified Reference Materials, merged in NIM (National Institute of Metrology) starting 1st January 2006, China, APMP |
| UNIIM |
Ural Scientific and Research Institute for Metrology, Rosstandart, Russian Federation, COOMET |
This page proposes print-out on A4 paper (portrait) of the comparison details (best printed out using a black and white printer).
Please, select items to be printed out, then click on "OK" :
CCQM-K34, CCQM-K34.1 and CCQM-K34.2
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
|
The key comparison reference value, xR, is calculated as the median of the participant results. Its standard uncertainty, uR, is based on the median of the absolute deviations, see on page 7 of the CCQM-K34 Final Report. xR = 4.89270 mol/kg, uR = 0.00016 mol/kg |
| The degree of equivalence of laboratory i relative to the key comparison reference value is given by a pair of terms, both expressed in mol/kg: Di = (xi - xR) and its expanded uncertainty Ui (k = 2) where Ui = 2(ui2 + uR2)1/2. |
| The degree of equivalence between two laboratories i and j is given by a pair of terms both expressed in mol/kg: Dij = (Di - Dj) = (xi - xj) and its expanded uncertainty Uij (k = 2) where Uij = 2(ui2 + uj2)1/2. |
|
SMU result is used as a link to the key comparison reference value from CCQM-K34. The results in the comparisons differ by less than 0.1 %, so the degrees of equivalence are directly comparable. |
| The degree of equivalence of participant i with respect to the key comparison reference value is given by a pair of terms, both expressed in mol/kg: Di = (DSMU-K34 + xi-K34.a - xSMU-K34.a) and its expanded uncertainty Ui (k = 2) where Ui = 2(uSMU-K34.a2 + ui-K34.a2 + uR2)1/2, with a = 1 or 2. |
| The degree of equivalence between BAM and laboratory j participant in CCQM-K34 is given by a pair of terms both expressed in mol/kg: DBAM, j = (DBAM - Dj) and its expanded uncertainty UBAM, j (k = 2) where UBAM, j = 2(uBAM-K34.12 + uSMU-K34.1 + uj2)1/2. Pair-wise degrees of equivalence involving CCQM-K34.2 participants are not calculated. |
CCQM-K34, CCQM-K34.1 and CCQM-K34.2
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
xi : result of measurement carried out by laboratory i
ui : combined standard uncertainty of xi
| Lab i | xi / (mol/kg) |
ui / (mol/kg) |
(ui / xi) |
Date of measurement |
| NMIJ | 4.89192 | 0.00074 |
0.0151 |
Jun / Jul 2004 |
| KRISS |
4.89259 |
0.00016 |
0.0034 |
Aug 2004 |
| SMU |
4.89269 |
0.00016 |
0.0033 |
Jul 2004 |
| NIM |
4.89272 |
0.00027 |
0.0056 |
Jul / Aug 2004 |
| NIST | 4.89298 | 0.00016 |
0.0034 |
Jul 2004 |
| UNIIM | 4.89458 | 0.00076 |
0.0155 |
Aug 2004 |
Graph of laboratory individual measurements :
xi and expanded uncertainties (k = 2)
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
xi-K34.1 : result of measurement carried out by laboratory i participating in CCQM-K34.1
ui-K34.1 : combined standard uncertainty of xi-K34.1
| Lab i | xi-K34.1 / (mol/kg) |
ui-K34.1 / (mol/kg) |
(ui-K34.1 / xi-K34.1) |
Date of measurement |
| BAM | 4.89530 | 0.00016 |
0.0033 |
May / Jun 2005 |
| SMU |
4.89520 |
0.00018 |
0.0037 |
May / Jun 2005 |
MEASURAND : Amount content of weak acid in potassium hydrogen phthalate
NOMINAL VALUE : ~ 4.897 mol/kg
xi-K34.2 : result of measurement carried out by laboratory i participating in CCQM-K34.2
ui-K34.2 : combined standard uncertainty of xi-K34.2
| Lab i | xi-K34.2 / (mol/kg) |
ui-K34.2 / (mol/kg) |
(ui-K34.2 / xi-K34.2) |
Date of measurement |
| INMETRO |
4.89643 |
0.00018 |
0.0036 |
Oct 2008 |
| UNIIM | 4.89656 | 0.00034 |
0.0070 |
Dec 2008 |
| SMU |
4.89683 |
0.00015 |
0.0031 |
Oct 2008 |
