Elemental analysis


Elemental analysis

Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each are present). Elemental analysis falls within the ambit of analytical chemistry, the set of instruments involved in decyphering the chemical nature of our world.

For synthetic chemists, elemental analysis or "EA" almost always refers to CHNX analysis — the determination of the percentage weights of carbon, hydrogen, nitrogen, and heteroatoms (X) (halogens, sulfur) of a sample. This information is important to help determine the structure of an unknown compound, as well as to help prove the structure and purity of a synthesized compound.

Methods

The most common form of elemental analysis, CHN analysis, is accomplished by combustion analysis. In this technique, a sample is burned in an excess of oxygen, and various traps collect the combustion products — carbon dioxide, water, and nitric oxide. The weights of these combustion products can be used to calculate the composition of the unknown sample.

Other quantitative methods include:
*Gravimetry, where the sample is dissolved and then the element of interest is precipitated and its mass measured or the element of interest is volatilized and the mass loss is measured.
*Optical atomic spectroscopy, such as flame atomic absorption, graphite furnace atomic absorption, and inductively coupled plasma atomic emission, which probe the outer electronic structure of atoms.

To qualitatively determine which elements exist in a sample, methods include:
* Mass spectrometric atomic spectroscopy, such as inductively coupled mass spectrometry, which probes the mass of atoms.
* Other spectroscopy which probes the inner electronic structure of atoms such as X-ray fluorescence, Particle-Induced X-ray Emission, x-ray photoelectron spectroscopy, and Auger electron spectroscopy.
*Electrochemical methods
** sodium fusion
** Schöniger oxidation


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • elemental analysis — elementinė analizė statusas T sritis Standartizacija ir metrologija apibrėžtis Cheminių elementų radimas ir jų kiekio nustatymas medžiagoje. atitikmenys: angl. elemental analysis; elementary analysis vok. Elementaranalyse, f rus. элементарный… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • elemental analysis — elementinė analizė statusas T sritis chemija apibrėžtis Cheminių elementų radimas ir nustatymas. atitikmenys: angl. elemental analysis; elementary analysis rus. элементный анализ …   Chemijos terminų aiškinamasis žodynas

  • elemental analysis — elementinė analizė statusas T sritis fizika atitikmenys: angl. elemental analysis; elementary analysis vok. Elementaranalyse, f rus. элементарный анализ, m; элементный анализ, m pranc. analyse élémentaire, f …   Fizikos terminų žodynas

  • analysis — /euh nal euh sis/, n., pl. analyses / seez /. 1. the separating of any material or abstract entity into its constituent elements (opposed to synthesis). 2. this process as a method of studying the nature of something or of determining its… …   Universalium

  • Elemental cost planning — is a system of Cost planning and Cost control, typically for buildings, which enables the cost of a scheme to be monitored during design development.It should : *Ensure that the tender amount is close to the first estimate, or that any likely… …   Wikipedia

  • Elemental Gimmick Gear — Infobox VG| title = Elemental Gimmick Gear developer = Hudson Soft publisher = Vatical Entertainment designer = engine = released = December 20, 1999 genre = Action RPG modes = Single player ratings = ESRB: Everyone (E) platforms = Dreamcast… …   Wikipedia

  • surface analysis — ▪ chemistry Introduction       in analytical chemistry (chemistry), the study of that part of a solid that is in contact with a gas or a vacuum. When two phases of matter are in contact, they form an interface. The term surface is usually… …   Universalium

  • Hair analysis — is the chemical analysis of a hair sample. Hair may be considered for retrospective purposes when blood and urine are no longer expected to contain a particular contaminant, typically a year or less. [Eastern Research Group. [http://www.atsdr.cdc …   Wikipedia

  • spectrochemical analysis — Any of a group of chemical analysis methods that depend on measurement of the wavelength and intensity of electromagnetic radiation. It is used chiefly to determine the arrangement of atoms and electrons in molecules on the basis of the amounts… …   Universalium

  • elementary analysis — elementinė analizė statusas T sritis Standartizacija ir metrologija apibrėžtis Cheminių elementų radimas ir jų kiekio nustatymas medžiagoje. atitikmenys: angl. elemental analysis; elementary analysis vok. Elementaranalyse, f rus. элементарный… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.