Inorganic carbon dioxide, calculation

In both TOC and dissolved organic carbon (DOC) determinations, OC in the water sample is oxidized to produce carbon dioxide (C02), which is then measured by a detection system. Inorganic carbon (IC) is removed prior to the analysis by acidifying the sample. Alternatively, TOC can be determined indirectly through the measurement of total carbon (TC) and IC. TOC in the indirect method is calculated as the difference between the two. 

The amount of C02 can be calculated from the difference of the concentrations of inorganic carbon dioxide at the beginning (6.64 mmol/L) and at the end of the channel (2.02 mmol/L). This amount is 4.62 mmol/L or 873.72 kg C/a. Furthermore, it is known that 3354.85 kg of calcite precipitate per year, which amounts to 402.58 kg of carbon per year (3354.85 kg/a / 100 mol/L (molecular weight of CaC03)12 mol/ L (molecular weight of carbon)). The difference between the initial carbon concentration and the concentration, that is lacking at... 

The crystals of such inorganic substances as carbon dioxide andjthe hydrogen halides and of the majority of organic substances are composed of molecules bound together by van der Waal s forces. If the molecule has a relatively simple structure and only a small polarity, the heat of sublimation is found to be small and for such molecules, London s has calculated the heats of sublimation assuming that only dispersion forces are responsible for the inter-molecular attraction. The attraction energy is considered to be given by =. — (7/r where r is the distance between the molecules and C = J aH (see equation 12.3). In addition to non-polar or weakly polar molecules,... 

In addition to these measurements the Theoretical Oxygen Demand (THOD) is also often calculated. This is done by calculating the amount of oxygen required to convert all organic substances to carbon dioxide and water. Additionally, oxidation of certain inorganic species to nitrate, sulfate... 

Use of table 3a in calculations of lanthanide seawater complexation requires that the total inorganic carbon concentration of seawater (Cr) be partitioned into dissolved aqueous carbon dioxide (C02aq), bicarbonate (HCOj) and carbonate (COj ). Since only a small fraction ( 14%) of COf in seawater is in the form of free ions, with the remainder being ion-paired as NaCOj, CaCO and MgCO, use of table 3a constants requires an assessment of carbonate and bicarbonate ion-pairing equilibria. Table 3b shows a more convenient stability constant formulation wherein lanthanide carbonate stability constants are expressed in terms of total (free plus ion-paired) carbonate ion concentrations in seawater ([C03"]t)- These results can be compared with direct observations of europium carbonate complexation in synthetic seawater (Lee and Byrne 1994). The GdCOj and Gd(C03)2 formation constant results of Lee and Byrne (1994), expressed in terms of... 

Carbon dioxide is, in many ways, an ideal gas for the mass spectrometry of oxygen (and carbon) isotopes. The memory effect is small and can usually be ignored unless very accurate analyses are required. It is easily handled and purified by sublimation on a vacuum line or by vapor-phase chromatography and is noncorrosive. Carbon dioxide can be formed from quite a number of inorganic and organic compounds without isotopic dilution, as will be described in due course. From the relative intensity of the ions of mass 44 (C 0 0 ), mass 45 (C 0 0 , Ci30i Oi ), and mass 46 (Ci20i 0 , Cl 0 0l Ci O O ), the concentration of can be calculated. 

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