The branch of chemistry concerned with identifying substances in a sample and measuring their quantities or concentrations. A bicinchoninic acid assay, for example, estimates protein content through an optical measurement.
The nonvolatile residue measured by a specified drying procedure; the drying conditions define the operational result.
Analysis based on measured absorption or transmission of light, interpreted through calibration and appropriate blanks.
Determination of the amounts or identities of chemical elements in an organic sample, distinguished from identifying its molecular structure.
Conversion of suitable covalently bound nitrogen, sulfur or halogens into species detectable in an aqueous extract. Incomplete conversion and interfering species require controls.
A preparation containing the reagents but excluding the sample, used to identify responses that do not originate with that sample.
The largely inorganic residue remaining after a specified ignition procedure. Its chemical forms need not be identical with the original mineral species in the sample.
An operational separation into material classes, such as lipid-soluble material, protein-rich residue and mineral matter, rather than a complete molecular inventory.
Identification of constituents or classes of constituents, distinguished from measuring their amounts.
Determination of carbon dioxide by absorption into standardized barium hydroxide and measurement of the remaining base. Barium carbonate must not be titrated as though it were residual hydroxide.
An alkaline tetraiodomercurate reagent used for colour-based detection and estimation of Ammonia, named after Julius Neßler.
Checks using blanks, standards, replicate measurements and recovery experiments to assess the performance of an analytical procedure.
Determination of an analyte amount from the measured amount of a standardized reagent reaching a specified titration endpoint.
Determination of a solution's effective concentration by reaction with a suitable reference material or another independently established standard.
Quantitative analytical chemistry using the measured volume of a standard solution and a known reaction proportion.
A chemical tracer is a constituent whose measured concentration reveals transport or other processes. An ocean box model can follow a chemical tracer through ocean circulation, with additional source and sink terms if the constituent is produced or removed internally. A passive, conservative chemical tracer changes only by transport and mixing.
A known amount of a reference substance added to a sample to support quantification and identify losses or instrumental variation. An isotope-labeled analogue can closely track the behavior of the analyte.
An assay that estimates protein concentration from a colour-producing chemical reaction, measured by absorbance and compared with known protein reference samples. Bovine serum albumin is commonly used as the reference protein. The readout estimates protein content rather than identifying each protein in a mixture.
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Analytical chemistry is a branch of chemistry focused on the qualitative and quantitative analysis of substances to understand their composition, structure, and properties. It involves a variety of techniques and methods to separate, identify, and quantify matter. Key aspects of analytical chemistry include: 1. **Qualitative Analysis**: Determining what substances are present in a sample. This involves identifying the chemical components or compounds without necessarily measuring their concentrations.
