Potassium atom emission

Fig. 13.9 Frequency dependence of potassium atom emission from argon-saturated 2 M KC1 aqueous solutions. Shown are normalized spectra measured at frequencies of 28, 115,...

Fig. 13.10 Sonoluminescence spectrum of potassium-atom emission from helium-saturated KC1 aqueous solution at 148 kHz. The spectrum shows slightly asymmetric broadening toward blue side, which is in contrast with the potassium line in argon-saturated solution...

It is reported [95] that the reaction of sodium vapour with chlorine produces emission from Na2 including many new bands of the red system of Na2, but that band emission from the sodium chloride does not occur. The flames of halogens burning in potassium emit the visible—UV systems of the potassium halide molecules and also substantial potassium atom emission. The extent of the emission implies that the direct reaction... 

Description of Method. Salt substitutes, which are used in place of table salt for individuals on a low-sodium diet, contain KCI. Depending on the brand, fumaric acid, calcium hydrogen phosphate, or potassium tartrate also may be present. Typically, the concentration of sodium in a salt substitute is about 100 ppm. The concentration of sodium is easily determined by flame atomic emission. Because it is difficult to match the matrix of the standards to that of the sample, the analysis is accomplished by the method of standard additions. 

Sodium and Potassium. Sodium and potassium can be deterrnined by either atomic emission or absorption. Large concentrations of sodium can interfere with the potassium deterrnination in either of these methods. Excess sodium can be added to both the potassium standards and samples to minimize any variations in the samples. Proper positioning of the flame helps reduce sodium interference in atomic absorption. 

Organogermanium compounds can be mineralized by wet oxidative digestion for 4 h at 70°C, in aqueous potassium persulphate, at pH 12. After dilution to an adequate concentration germanium can be determined by ICP-AES (inductively coupled plasma atomic emission spectrometry)9. 

All four dissolution procedures studied were found to be suitable for arsenic determinations in biological marine samples, but only one (potassium hydroxide fusion) yielded accurate results for antimony in marine sediments and only two (sodium hydroxide fusion or a nitricperchloric-hydrofluoric acid digestion in sealed Teflon vessels) were appropriate for determination of selenium in marine sediments. Thus, the development of a single procedure for the simultaneous determination of arsenic, antimony and selenium (and perhaps other hydride-forming elements) in marine materials by hydride generation inductively coupled plasma atomic emission spectrometry requires careful consideration not only of the oxidation-reduction chemistry of these elements and its influence on the hydride generation process but also of the chemistry of dissolution of these elements. 

Atomic emission spectroscopy plays an important role in the control of sodium, potassium and lithium in a number of raw materials and formulations. 

To investigate the effect of potassium on the analysis of sodium by atomic emission spectrometry. 

An official method has been published for the determination of nickel in 1M ammonium nitrate extracts of potassium from soil [178]. The level of potassium in the extract is determined by flame photometry. Inductively coupled plasma atomic emission spectrometry (Sect. 2.55) and stable isotope dilution (Sect. 2.55) have been applied to the determination of potassium in multi-metal analyses. 

This instrument has allowed several studies that provide information not obtainable by other means to be conducted. Four examples are presented as follows The first example concerns the question of the mechanism of emission of potassium ions from potassium zeolite [7]. Earlier studies had made the assumption that this was an S-L type of ion formation mechanism [8], implying that there was a neutral potassium atom flux accompanying the flux of atomic potassium cations. Experiments performed on this instrument clearly showed that this is not the case there was no detectable neutral atomic potassium flux accompanying the cation flux. Thus this instrument was used to answer a long-standing question with an experiment conducted in one afternoon and allowed the conclusion to be reached that the mechanism is potassium ions in the solid state subliming into the gas phase. 

N. Carrion, A. Itriago, M. Murillo, E. Eljuri, A, Fernandez, Determination of calcium, potassium, magnesium, iron, copper and zinc in maternal milk by inductively coupled plasma atomic emission spectrometry, J. Anal. Atom. Spectrom., 9 (1994), 205-207. 

M. C. Valdes-Hevia y Temprano, M. R. Fernandez de la Campa, A. Sanz-Medel, Sensitive method for determination of lead by potassium dichromate-lactic acid hydride generation inductively coupled plasma atomic emission spectrometry, J. Anal. Atom Spectrom., 8 (1993), 821-825. 

Inorganic extractables/leachables would include metals and other trace elements such as silica, sodium, potassium, aluminum, calcium, and zinc associated with glass packaging systems. Analytical techniques for the trace analysis of these elements are well established and include inductively coupled plasma—atomic emission spectroscopy (ICP-AES), ICP-MS, graphite furnace atomic absorption spectroscopy (GFAAS), electron microprobe, and X-ray fluorescence. Applications of these techniques have been reviewed by Jenke. " An example of an extractables study for certain glass containers is presented by Borchert et al. ". ... 

The concentrations of alkali metals and chlorine were determined directly for the fuel samples using a inductively coupled plasma-atomic emission spectrometry apparatus in order to analyse sodium and potassium contents. Chlorine content was determined by Eschka method according to ASTM D2361-66. The concentrations are given on dry basis (table 1). 

E532 Kulpmann, W.R. (1989). Influence of protein on the determination of sodium, potassium and chloride in serum by Ektachem DT 60 with the DTE Module Evaluation with special attention to a possible protein error by flame atomic emission spectrometry and ion-selective electrodes proposals to their calibration. J. Clin. Chem. Clin. Biochem. 27, 815-824. 

Both atomic and molecular emission and absoiption can be measured when a sample is atomized in a flame. A typical flame-emission spectrum was shown in Figure 24-19. Atomic emissions in this spectrum are made up of narrow lines, such as that for sodium at about 330 nm, potassium at approximately 404 nm, and calcium at 423 nm. Atomic spectra are thus called line spectra. Also present are emission bands that result from excitation of molecular species such as MgOH, MgO, CaOH, and OH. Here, vibrational transitions superimposed on electronic transitions produce... 

For example, we showed in earlier chapters that the calcium ion concentration of an aqueous solution is readily determined by titration with a standard EDTA solution or by potential measurements with a specific-ion electrode. Alternatively, the calcium content of a solution can be determined either from atomic absorption or atomic emission measurements or by the precipitation of calcium oxalate followed by weighing or titrating with a standard solution of potassium permanganate. 

M.I.G.S. Almeida, M.A. Segundo, J.L.F.C. Lima, A.O.S.S. Rangel, Interfacing multi-syringe flow injection analysis to flame atomic emission spectrometry an intelligent system for automatic sample dilution and determination of potassium, J. Anal. At. Spectrom. 24 (2009) 340. 

Emission from electronically excited TiO molecules has been observed by Palmer and co-workers from the reaction of titanium tetrachloride or tetrabromide with potassium vapour in the presence of oxygen [277] and of nitrous oxide [278]. The potassium atoms presumably strip the halogen atoms from the titanium tetrahalide, and the titanium atoms then react with the oxygen or nitrous oxide producing electronically excited TiO molecules. 

Potassium analysis is usually carried out by flame spectrometry. Atomic emission spectrometry (AES) is slightly more sensitive, though atomic absorption spectrometry (AAS) is somewhat more immune to interference. Interferences occur in the presence of high concentrations of sodium and due to the formation of refractory potassium phosphates in the flame. A solution containing 0.4 mmol cesium chloride and 0.15 mmolL lanthanum nitrate dissolved in 0.1 M HCl will reduce both cation enhancement and anionic suppression (Wieland 1992, Birch and Padgham 1993). 

Thienpont LM, Van Nuwenboeg JE, Reinauee H and Stockl D (1996) Validation of candidate reference methods based on ion chromatography for determination of total sodium, potassium, calcium and magnesium in serum through comparison with flame atomic emission and absorption spectrometry. Clin Biochem 29 501-508. 

Atom-ion equilibria in flames create a number of important consequences in flame spectroscopy, b or example, intensities ol atomic emission or absorption lines for the alkali metals, particularly potassium, rubidium, and cesium, are affected by leniperalure in a complex way. Increased temperature cause an increase in the population of excited atoms, according lo the Boltzmann relationship (Kqualion S-l). Counteracting this effect, however, is a decrease in concentration of atoms resulting from ionization. Thus, under some circumstances a decrease in emission or abst>rp-lion may be observed in hotter flames. It is or this reason that lower e.xciialion Icmperaliircs are usually spcciliod for the deierminaiion of alkali metals. 

Sodium and potassium in serum are determined in the clinical laboratory by atomic-emission spectroscopy, using an instrument designed specifically for this purpose [5]. Two filter monochromators isolate the sodium and potassium emission lines. A lithium internal standard is used, and the ratios of the Na/Li and K/Li signals are read out on two separate meters. The internal standard compensates for minor fluctuations in flame temperature, aspiration rate, and so forth. A cool flame, such as air-propane, is used to minimize ionization. Typically, the serum sample and standards are diluted 1 200 with a 100 ppm Li solution and aspirated directly. The instrument can be adjusted to read directly in meq/1 for sodium and potassium by adjusting the gain while aspirating appropriate standards. 

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