Archer, MDe Vos, BJVisser, MS2007-07-022007-07-022007-04Archer, M, De Vos, BJ and Visser, MS. 2007. Preparation, assay and certification of aqueous ethanol reference solutions. Accreditation and Quality Assurance, Vol. 12(3-4), pp 188-1930949-1775http://hdl.handle.net/10204/834http://www.springerlink.com/content/k61xlj60250h328p/?p=b7ac90323ec2460985dfcd591f22e41e&pi=11Internationally, certified ethanol reference materials are required to calibrate breathalysers and blood-alcohol measurement instruments. The CSIR National Metrology Laboratory of South Africa provides certified aqueous ethanol solutions with traceability to the SI. Ethanol solutions in the concentration range 10 mg/100 g to 20 g/100 g are prepared gravimetrically by mixing ethanol and reagent quality water. To verify the concentration of the ethanol it is oxidized to acetic acid with potassium dichromate in the presence of sulphuric acid. The unreacted potassium dichromate is back-titrated with sodium thiosulphate. The method utilizes gravimetry and titrimetry, which are both primary methods. This paper addresses aspects of ethanol-certified reference materials that have not been previously published: traceability, stability of unpreserved ethanol solutions, homogeneity, quality control measures and the effect of reproducibility on the measurement uncertaintyenEthanolCertified reference materialsTraceabilityTitrimetryGravimetryPrimary methodsArticleArcher, M., De Vos, B., & Visser, M. (2007). Preparation, assay and certification of aqueous ethanol reference solutions. http://hdl.handle.net/10204/834Archer, M, BJ De Vos, and MS Visser "Preparation, assay and certification of aqueous ethanol reference solutions." (2007) http://hdl.handle.net/10204/834Archer M, De Vos B, Visser M. Preparation, assay and certification of aqueous ethanol reference solutions. 2007; http://hdl.handle.net/10204/834.TY - Article AU - Archer, M AU - De Vos, BJ AU - Visser, MS AB - Internationally, certified ethanol reference materials are required to calibrate breathalysers and blood-alcohol measurement instruments. The CSIR National Metrology Laboratory of South Africa provides certified aqueous ethanol solutions with traceability to the SI. Ethanol solutions in the concentration range 10 mg/100 g to 20 g/100 g are prepared gravimetrically by mixing ethanol and reagent quality water. To verify the concentration of the ethanol it is oxidized to acetic acid with potassium dichromate in the presence of sulphuric acid. The unreacted potassium dichromate is back-titrated with sodium thiosulphate. The method utilizes gravimetry and titrimetry, which are both primary methods. This paper addresses aspects of ethanol-certified reference materials that have not been previously published: traceability, stability of unpreserved ethanol solutions, homogeneity, quality control measures and the effect of reproducibility on the measurement uncertainty DA - 2007-04 DB - ResearchSpace DP - CSIR KW - Ethanol KW - Certified reference materials KW - Traceability KW - Titrimetry KW - Gravimetry KW - Primary methods LK - https://researchspace.csir.co.za PY - 2007 SM - 0949-1775 T1 - Preparation, assay and certification of aqueous ethanol reference solutions TI - Preparation, assay and certification of aqueous ethanol reference solutions UR - http://hdl.handle.net/10204/834 ER -