Calcium qualitative analysis

This is used extensively for qualitative analysis, for it is a rapid process and requires simple apparatus. The adsorbent is usually a layer, about 0 23 mni. thick, of silica gel or alumina, with an inactive binder, e.g. calcium sulphate, to increase the strength of the layer.. A. i i slurry of the absorbent and methanol is commonly coated on glass plates (5 20 cm. or 20 x 20 cm.), but microscope... 

In similar circumstances, silver salts leave a residue of metallic silver lead and copper salts usually leave a residue of the corresponding oxide calcium and barium salts leave a resirlne of the carbonate or oxide. Identify the metal in all such cases by the usual tests of qualitative inorganic analysis. Metals other than the above are seldom encountered in elementan qualitative analysis. 

Mars yellow may be distinguished from ochre by qualitative analysis, especially by the tests for calcium sulphate, alumina as such, and zinc oxide. 

Qualitative Analysis.—The minium is treated with dilute nitric acid effervescence indicates carbonates in the solution the lead is precipitated by means of hydrogen sulphide, the filtrate being tested for zinc, iron, aluminium, calcium and magnesium by the ordinary methods. The brown residue insoluble in nitric acid is heated further with nitric add in presence of either sugar solution or hydrogen peroxide until the lead dioxide is completely dissolved any insoluble residue then remaining may contain lead sulphate, barium sulphate or clay, which may be identified in the usual way. 

Ash.—The dry residue from the determination of the water is incinerated and the ash weighed. If this exceeds 1%, adulteration with mineral matter is probable, this being confirmed by qualitative analysis of the ash. Such analysis is useful in any case to detect the presence of heavy metals (especially iron), which may be introduced during the manufacturing processes and are harmful in the dyeing. The ash of alizarin consists normally of sodium or calcium salts. 

In qualitative analysis, calcium is detected spectroscopically using the red resonance line at 622.0 nm and the green line at... 

The human eye is a useful detector for qualitative analysis but not for quantitative analysis. Replacing the human eye with a spectrometer and photon detector such as a PMT or CCD permits more accurate identification of the elements present because the exact wavelengths emitted by the sample can be determined. In addition, the use of a photon detector permits quantitative analysis of the sample. The wavelength of the radiation indicates what element is present, and the radiation intensity indicates how much of the element is present. Flame atomic emission spectrometry is particularly useful for the determination of the elements in the first two groups of the periodic table, including sodium, potassium, lithium, calcium, magnesium, strontium, and barium. The determination of these elements is often called for in medicine, agriculture, and animal science. Remember that the term spectrometry is used for quantitative analysis by the measurement of radiation intensity. 

Edwards et al. (1958) have used infrared spectroscopy in the qualitative analysis of 30 specimens of human biliary calculi. The spectra of cholesterol, calcium bilirubinate, and calcium carbonate display prominent and characteristic bands that do not overlap in certain areas of the spectrum. Bands at 3380, 2910, and 1055cm" indicate the presence of cholesterol, a doublet at 1670 and 1630 cm" is characteristic of calcium bilirubinate, and a sharp band at 875 cm is produced by calcium carbonate. It is thus possible to verify the principal constituents of biliary calculi—whether they are (1) pure gallstones that are composed of either cholesterol, calcium bilirubinate, or calcium carbonate, or are (2) mixed gallstones that are composed chiefly of two or three of these components, or are (3) combined llstones with a nucleus of one kind and a shell of another substance. 

Usuki (169) raised rabbits on a diet deficient in fat-soluble vitamins and found a 9% incidence of gallstones after 6-8 weeks. Qualitative analysis revealed that these small sandlike stones contained calcium, bilirubin, and traces of cholesterol. 

Detection of halogens. Very few organic compounds contain halogen atoms which form halide ions in aqueous solutions and so can be detected by the addition of silver ion. It is necessary, therefore, to convert the organic halogen to a metallic halide by fusion with metallic sodium or calcium oxide. By such decomposition nitrogen and sulfur, if present, form ions which can be detected by the usual methods of qualitative inorganic analysis. 

Nitric peroxide, determination of, stability test for explosives, 83 Nitroarornatic compounds, analysis ot 43 separation from nitroglycerine. 52 Nilrucellulo.< e, analysis of, 32 calcium carbonate, 32 cellulose (unnitrate a). 37 mercury, 38 n.ineral matter, 32 moisture, 32 nitrogen, 33, 51 parntTm nax, 33 pulp, stability tests, 74 qualitative tests, 50 solubility in ether alcohol, 39 stfllrtlity tests, 33, 73, 74, 83 sulphates, 3 ... 

The thermal decomposition of 14 model mixtures of drug excipients was studied by TG. DTG. and DTA by Wesolowski (96). Qualitative determination of pharmaceutical preparations containing various amounts of phenyl salicylate, nitrofurantoin, and calcium gluconate was carried out by use of DTA. Wesolowski. by the TG method, determined the quantitative analysis of these mixtures by using the relationship... 

The evolution of hydration and carbonation of powder samples was assessed by XRD, mercury intrusion porosimetry (MIP), FTIR, DTA/TG, EDXRF and SEM. By identifying calcium silicate hydrates (CSH) and calcium aluminate hydrates (CAH) at different ages, not only qualitatively, but also semi-quantitatively, the hydration and carbonation processes could be monitored. The mineralogical analysis was investigated by XRD with a Siemens D-500 diffractometer (40 kV/35 mA) the spectra were collected... 

At low and medium supersaturations, hydrophilic cations form different crystal hydrates by heterogeneous nucleation and subsequent crystal growth and phase transformation. Dehydration curves give information on the modes of water incorporation resulting from different modes of crystallization. A useful application of thermal analysis is the analytical approach by determining the mass loss due to dehydration, it was possible to quantitatively determine the proportion of different calcium oxalate hydrates in mixtures, which have been qualitatively analyzed by other techniques (X-ray powder diffraction, IR spectroscopy, etc.). The method yielded excellent results in studies of the kinetics of phase transformation and has been successfully used to demonstrate the potential of surfactant micelles to control the nature of the crystallizing phase. 

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