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Making a saline water solution by dissolving table salt in water.The salt is the solute and the water the solvent. In chemistry, a solution is defined by IUPAC as "A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the solvent, is treated differently from the other substances, which are called solutes.
In chemistry, a reagent (/ r i ˈ eɪ dʒ ən t / ree-AY-jənt) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. [1] The terms reactant and reagent are often used interchangeably, but reactant specifies a substance consumed in the course of a chemical reaction. [ 1 ]
If the amount in the sample is below an instrument's range of measurement, the method of addition can be used. In this method, a known quantity of the element or compound under study is added, and the difference between the concentration added and the concentration observed is the amount actually in the sample.
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). A reagent, termed the titrant or titrator, [2] is prepared as a standard solution of known concentration and volume.
Reagent Chemicals [a] is a publication of the American Chemical Society (ACS) Committee on Analytical Reagents, [1] detailing standards of purity for over four hundred of the most widely used chemicals in laboratory analyses and chemical research. Chemicals that meet this standard may be sold as "ACS Reagent Grade" materials.
An assay (analysis) is never an isolated process, as it must be accompanied with pre- and post-analytic procedures. Both the communication order (the request to perform an assay plus related information) and the handling of the specimen itself (the collecting, documenting, transporting, and processing done before beginning the assay) are pre-analytic steps.
Chemical tests use reagents to indicate the presence of a specific chemical in an unknown solution. The reagents cause a unique reaction to occur based on the chemical it reacts with, allowing one to know what chemical is in the solution. An example is Heller's test where a test tube containing proteins has strong acids added to it.
The general expression Qualitative Analysis [...] refers to analyses in which substances are identified or classified on the basis of their chemical or physical properties, such as chemical reactivity, solubility, molecular weight, melting point, radioactivity properties (emission, absorption), mass spectra, nuclear half-life, etc. Quantitative Analysis refers to analyses in which the amount ...