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Espectroscopía de Emisión Atómica

Atomic emission spectroscopy (AES) is a method of chemical analysis that uses the intensity of light emitted from a flame, plasma, arc, or spark at a particular wavelength to determine the quantity of an element in a sample. The wavelength of the atomic spectral line gives the identity of the element while the intensity of the emitted light is proportional to the number of atoms of the element.

Flame emission spectroscopy

A flame during the assessment of calcium ions in a flame photometer

A sample of a material (analyte) is brought into the flame as either a gas, sprayed solution, or directly inserted into the flame by use of a small loop of wire, usually platinum. The heat from the flame evaporates the solvent and breaks chemical bonds to create free atoms. The thermal energy also excites the atoms into excited electronic states that subsequently emit light when they return to the ground electronic state. Each element emits light at a characteristic wavelength, which is dispersed by a grating or prism and detected in the spectrometer.

A frequent application of the emission measurement with the flame is the regulation of alkali metals for pharmaceutical analytics.​

Inductively coupled plasma atomic emission spectroscopy

Inductively coupled plasma atomic emission spectroscopy (ICP-AES) uses an inductively coupled plasma to produce excited atoms and ions that emit electromagnetic radiation at wavelengths characteristic of a particular element.​​

Advantages of ICP-AES are excellent limit of detection and linear dynamic range, multi-element capability, low chemical interference and a stable and reproducible signal. Disadvantages are spectral interferences (many emission lines), cost and operating expense and the fact that samples typically must be in solution.

Spark and arc atomic emission spectroscopy

Spark or arc atomic emission spectroscopy is used for the analysis of metallic elements in solid samples. For non-conductive materials, the sample is ground with graphite powder to make it conductive. In traditional arc spectroscopy methods, a sample of the solid was commonly ground up and destroyed during analysis. An electric arc or spark is passed through the sample, heating it to a high temperature to excite the atoms within it. The excited analyte atoms emit light at characteristic wavelengths that can be dispersed with a monochromator and detected. In the past, the spark or arc conditions were typically not well controlled, the analysis for the elements in the sample were qualitative. However, modern spark sources with controlled discharges can be considered quantitative. Both qualitative and quantitative spark analysis are widely used for production quality control in foundries and steel mills.

See also

• Inductively coupled plasma atomic emission spectroscopy
• Atomic absorption spectroscopy
• Atomic spectroscopy
• Laser-induced breakdown spectroscopy

Bibliography

• Reynolds, R. J.; Thompson, K. C. (1978). Atomic absorption, fluorescence, and flame emission spectroscopy: a practical approach. New York: Wiley. ISBN 0-470-26478-0. 
• Uden, Peter C. (1992). Element-specific chromatographic detection by atomic emission spectroscopy. Columbus, OH: American Chemical Society. ISBN 0-8412-2174-X. 

External links

• Atomic Emission Spectroscopy Tutorial
• Wikimedia Commons alberga una categoría multimedia sobre Iaralúa/Taller.

[[Category:Emission spectroscopy] [[Category:Scientific techniques] [[Category:Analytical chemistry]

Atomic emission spectroscopy (AES) is a method of chemical analysis that uses the intensity of light emitted from a flame, plasma, arc, or spark at a particular wavelength to determine the quantity of an element in a sample. The wavelength of the atomic spectral line gives the identity of the element while the intensity of the emitted light is proportional to the number of atoms of the element.

Flame emission spectroscopy

A flame during the assessment of calcium ions in a flame photometer

A sample of a material (analyte) is brought into the flame as either a gas, sprayed solution, or directly inserted into the flame by use of a small loop of wire, usually platinum. The heat from the flame evaporates the solvent and breaks chemical bonds to create free atoms. The thermal energy also excites the atoms into excited electronic states that subsequently emit light when they return to the ground electronic

state. Each element emits light at a characteristic wavelength, which is dispersed by a grating or prism and detected in the spectrometer.

A frequent application of the emission measurement with the flame is the regulation of alkali metals for pharmaceutical analytics.​

Inductively coupled plasma atomic emission spectroscopy

Inductively coupled plasma atomic emission spectroscopy (ICP-AES) uses an inductively coupled plasma to produce excited atoms and ions that emit electromagnetic radiation at wavelengths characteristic of a particular element.​​

Advantages of ICP-AES are excellent limit of detection and linear dynamic range, multi-element capability, low chemical interference and a stable and reproducible signal. Disadvantages are spectral interferences (many emission lines), cost and operating expense and the fact that samples typically must be in solution.

Spark and arc atomic emission spectroscopy

Spark or arc atomic emission spectroscopy is used for the analysis of metallic elements in solid samples. For non-conductive materials, the sample is ground with graphite powder to make it conductive. In traditional arc spectroscopy methods, a sample of the solid was commonly ground up and destroyed during analysis. An electric arc or spark is passed through the sample, heating it to a high temperature to excite the atoms within it. The excited analyte atoms emit light at characteristic wavelengths that can be dispersed with a monochromator and detected. in the past, the spark or arc conditions were typically not well controlled, the analysis for the elements in the sample were qualitative. However, modern spark sources with controlled discharges can be considered quantitative. Both qualitative and quantitative spark analysis are widely used for production quality control in foundries and steel mills.

See also

• Inductively coupled plasma atomic emission spectroscopy
• Atomic absorption spectroscopy
• Atomic spectroscopy
• Laser-induced breakdown spectroscopy

Bibliography

• Reynolds, R. J.; Thompson, K. C. (1978). Atomic absorption, fluorescence, and flame emission spectroscopy: a practical approach. New York: Wiley. ISBN 0-470-26478-0. 
• Uden, Peter C. (1992). Element-specific chromatographic detection by atomic emission spectroscopy. Columbus, OH: American Chemical Society. ISBN 0-8412-2174-X. 

External links

• Atomic Emission Spectroscopy Tutorial
• Wikimedia Commons alberga una categoría multimedia sobre Iaralúa/Taller.
• Espectrometría.com

Espectroscopía de emisión atómica

La Espectroscopía de emisión atómica es un método de análisis químico que utiliza la intensidad de la luz emitida desde una llama, plasma, arco o chispa en una longitud de onda particular para determinar la cantidad de un elemento en una muestra. La longitud de onda de la línea espectral atómica da la identidad del elemento, mientras que la intensidad de la luz emitida es proporcional a la cantidad de átomo s del elemento.

Espectroscopía de emisión de llama Ensayo a la llama para la detección de calcio

Una muestra de un material (analito) se pone en la llama, ya sea como gas, solución pulverizada, o directamente insertado en la llama por el uso de un pequeño bucle de alambre, normalmente de platino. El calor de la llama evapora el disolvente y se rompen los enlaces químicos para crear átomos libres. La energía térmica también excita los electrones a estados electrónicos de mayor energía que posteriormente emiten luz cuando vuelven al estado fundamental. Cada elemento emite luz a una longitud de onda característica, que se dispersa por una rejilla o un prisma y se detecta en el espectrómetro.

Una aplicación frecuente de la medición de las emisiones con la llama es la regulación de los metales alcalinos para análisis farmacéuticos1 Espectrometría de emisión atómica de plasma acoplado inductivamente

Espectrometría de emisión atómica de plasma acoplado inductivamente (ICP-AES) utiliza plasma acoplado inductivamente para producir electrones excitados e iones que emiten [radiación electromagnética []] en longitudes de onda característica de un particular, [Elemento químico [| elemento]].2 3

Ventajas de ICP-AES: presenta excelentes límites de detección y rango dinámico lineal, capacidad multi-elemento, interferencia química baja y una señal estable y reproducible. Las desventajas son las interferencias espectrales (muchas líneas de emisión), los gastos y costos de operación y el hecho de que las muestras normalmente deben estar en solución. Espectroscopía de emisión atómica de Spark y arco

[La espectroscopía de emisión atómica de descarga electrostática Spark o arco eléctrico se utiliza para el análisis de elementos metálicos en muestras sólidas. Para los materiales no conductores, la muestra se muele con grafito en polvo para que sea conductor. En los métodos de espectroscopía de arco tradicionales, una muestra del sólido comúnmente se pulveriza y destruye durante el análisis. Un arco eléctrico o chispa se pasa a través de la muestra, calentándola a una temperatura alta para excitar los electrones dentro de ella. Los electrones del analito excitados emiten luz en longitudes de onda características que se pueden dispersar con un monocromador y se detecta. En el pasado, las condiciones de chispa o arco no fueron bien controlados, el análisis de los elementos de la muestra eran cualitativos. Sin embargo, fuentes de chispas modernas con descargas controladas pueden ser considerados cuantitativos. Tanto el análisis cualitativo y cuantitativo de chispa son ampliamente utilizados para el control de calidad de la producción en las fundiciones y acerías. Bibliografía

Reynolds, R. J .; Thompson, KC (1978). Atómica absorción, fluorescencia, y la llama espectroscopia de emisión: un enfoque práctico. Nueva York: Wiley. ISBN 0-470-26478-0. Texto « Consultado» ignorado (ayuda)

Uden, Peter C. (1992). Elemento específico cromatográfico detección por espectrometría de emisión atómica. Columbus, OH: Sociedad Americana de Química. ISBN 0-8412 -2174-X. Texto « Consultado» ignorado (ayuda)

Referencias

• Stáhlavská A (abril de 1973). «[The use of spectrum analytical methods in drug analysis. 1. Determination of alkaline metals using emission flame photometry]» (en alemán). Pharmazie 28 (4): pp. 238–9. PMID 4716605.
• Stefánsson A, Gunnarsson I, Giroud N (2007). «New methods for the direct determination of dissolved inorganic, organic and total carbon in natural waters by Reagent-Free Ion Chromatography and inductively coupled plasma atomic emission spectrometry». Anal. Chim. Acta 582 (1): pp. 69–74. doi:10.1016/j.aca.2006.09.001. PMID 17386476.
• Mermet, J. M. (2005). «Is it still possible, necessary and beneficial to perform research in ICP-atomic emission spectrometry?». J. Anal. At. Spectrom. 20: pp. 11–16. doi:10.1039/b416511j.|url=http://www.rsc.org/publishing/journals/JA/article.asp?doi=b416511j%7Cformat=%7Caccessdate=2007-08-31

Enlaces externos

Espectroscopia de Emisión Atómica Tutorial