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Electrolysis refers to the breakdown of substances using an electric current. This removes impurities in a substance that an electric current is run through; Sublimation is the process of changing of any substance (usually on heating) from a solid to a gas (or from gas to a solid) without passing through liquid phase. In terms of purification ...
While the term chemical substance is a precise technical term that is synonymous with chemical for chemists, the word chemical is used in general usage to refer to both (pure) chemical substances and mixtures (often called compounds), [14] and especially when produced or purified in a laboratory or an industrial process.
The Schiff test detects aldehydes; Tollens' reagent tests for aldehydes (known as the silver mirror test) The Zeisel determination tests for the presence of esters or ethers; Lucas' reagent is used to distinguish between primary, secondary and tertiary alcohols. The bromine test is used to test for the presence of unsaturation and phenols.
Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture. [1] In preparative chromatography, GC can be used to prepare pure compounds from a mixture. [2] [3] Gas chromatography is also sometimes known as vapor-phase chromatography (VPC), or gas–liquid partition chromatography ...
In chemistry, chemical purity is the measurement of the amount of impurities found in a sample.Several grades of purity are used by the scientific, pharmaceutical, and industrial communities.
Schematics of a simple mass spectrometer with sector type mass analyzer. This one is for the measurement of carbon dioxide isotope ratios as in the carbon-13 urea breath test. A mass spectrometer consists of three components: an ion source, a mass analyzer, and a detector. The ionizer converts a portion of the sample into ions. There is a wide ...
Any substance consisting of two or more different types of atoms (chemical elements) in a fixed stoichiometric proportion can be termed a chemical compound; the concept is most readily understood when considering pure chemical substances.
Firstly, a pure chemical should appear in at least one chemical phase and can also be characterized by its phase diagram. Secondly, a pure chemical should prove to be homogeneous (i.e., a uniform substance that has the same composition throughout the material [2]). The perfect pure chemical will pass all attempts to separate and purify it further.