فروش بافر 10 مرک 109438, Buffer solution10

Specification

Certipur^® Certified Reference Material

Producer:

Merck KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany.

Accreditation:

Merck KGaA, Darmstadt, Germany is accredited by the German

accreditation authority DAkkS as registered reference material producer D-RM-15185-01-00 in accordance with ISO Guide 34 and registered calibration laboratory D-K-15185-01-00 according to DIN EN ISO/IEC17025.

Minimum shelf life:                        3 years

(Laboratory manager)

1.09438.1000

Application and correct use:  This reference material is intended for use as a calibration standard for pH instruments or pH electrodes or as a control sample for measuring the pH value. The pH value is strongly dependent on the temperature. It is therefore necessary to keep the temperature constant within the measurement. Details concerning the nature of any hazard and appropriate precautions to be taken are provided in the material safety data sheet.

Expanded uncertainty UCRM:    The expanded uncertainty UCRM is calculated as UCRM = k ·uCRM, where k = 2 is the coverage factor for a 95% coverage probability and uCRM is the combined standard uncertainty in accordance to ISO Guide 34.

The combined standard uncertainty uCRM is obtained from the standard uncertainties of the characterisation, the homogeneity and the stability. uCharacterisationis the uncertainty in accordance to DIN EN ISO/IEC 17025

which includes the contributions of the primary reference material and the measuring system.

is the between-bottle variation in accordance to

ISO Guide 34. The assessment of homogeneity is performed

by analysis of a representative number of systematically

chosen sample units

is the uncertainty obtained from short-term and long-term stability in accordance to ISO Guide 34. The stability studies are the basis for the quantification of the minimum shelf life of this reference material for the unopened bottle.