Search results
Results from the WOW.Com Content Network
A primary standard in metrology is a standard that is sufficiently accurate such that it is not calibrated by or subordinate to other standards. Primary standards are defined via other quantities like length, mass and time. Primary standards are used to calibrate other standards referred to as working standards. [1] [2] See Hierarchy of Standards.
ISO 2597-1:2006 Part 1: Titrimetric method after tin(II) chloride reduction; ISO 2597-2:2019 Part 2: Titrimetric methods after titanium(III) chloride reduction; ISO 2598 Iron ores — Determination of silicon content ISO 2598-1:1992 Part 1: Gravimetric methods; ISO 2598-2:1992 Part 2: Reduced molybdosilicate spectrophotometric method
An example of a secondary standard is sodium hydroxide, a hydroscopic compound that is highly reactive with its surroundings. The concentration of a standard solution made with sodium hydroxide may fluctuate overtime due to the instability of the compound, requiring for calibration using a primary standard before use.
This is a list of published [note 1] standards and other deliverables of the International Organization for Standardization (ISO). [note 2] For a complete and up-to-date list of all the ISO standards, see the ISO catalogue. [1] The standards are protected by copyright and most of them must be purchased.
An example of a primary standard was the international prototype of the kilogram (IPK) which was the master kilogram and the primary mass standard for the International System of Units (SI). The IPK is a one kilogram mass of a platinum-iridium alloy maintained by the International Bureau of Weights and Measures (BIPM) in Sèvres, France.
ISO/IEC GUIDE 3:1981 Identification of national standards that are equivalent to International Standards [Withdrawn: replaced with ISO/IEC GUIDE 21:1999, now ISO/IEC GUIDE 21-1:2005 and ISO/IEC GUIDE 21-2:2005] ISO 4:1997 Information and documentation — Rules for the abbreviation of title words and titles of publications
These standards are conventionally accepted as best practice and used globally by industry and organizations. In circumstances and situations there are certain methods and systems that are used as benchmarks, guidelines or protocols for communication , measurement , orientation , reference for information , science , symbols and time .
A burette and Erlenmeyer flask (conical flask) being used for an acid–base titration.. Titration (also known as titrimetry [1] and volumetric analysis) is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed).