Determination inorganic acidity

When we use any substance as a solvent for a protonic acid, the acidic and basic species produced by dissociation of the solvent molecules determine the limits of acidity or basicity in that solvent. Thus, in water, we cannot have any substance or species more basic than OH or more acidic than H30 in liquid ammonia, the limiting basic entity is NHf, the acidic is NH4. Many common inorganic acids, for example HCl, HNO3, H2SO4 are all equally strong in water because their strengths are levelled to that of the solvent species Only by putting them into a more acidic... 

Molybdates yield sparingly soluble orange-yellow molybdyl oxinate with oxine solution the pH of the solution should be between the limits 3.3-7.6. The complex differs from other oxinates in being insoluble in organic solvents and in many concentrated inorganic acids. The freshly precipitated compound dissolves only in concentrated sulphuric acid and in hot solutions of caustic alkalis. This determination is of particular interest, as it allows a complete separation of molybdenum from rhenium. 

Since the early 1990s an increasing number of papers has been devoted to the application of CE for the analysis of both inorganic cations [906-915] and low-molecular-mass anions [915-922]. Standard CE methods have been developed and validated for determining inorganic anions (e.g. chloride, sulfate and nitrate), small carboxylic acids and metal ions that all have limited or no UV absorbance. In those situations, short UV wavelengths (190 nm) or indirect UV detection should be used. Such methods might be extended to metallic... 

The surface activation time of the polymer required for maximum site activity for binding antibodies was determined by evaluating the fluorescence intensity of a series of probes incubated in inorganic acids at different times. Knowledge of the surface activation time is necessary to obtain maximum activation, thus allowing maximum antibody immobilization on the probe. Consequently, lower detection limits may be achieved. 

It has been postulated that sulfuric acid may produce tumors by direct genotoxic effects of lowered pH or may promote carcinogenesis by inducing chronic tissue irritation. lARC has determined that there is sufficient evidence that occupational exposure to strong inorganic acid mists containing sulfuric acid is carcinogenic to humans. ... 

Procedure (extraction). Transfer 2.5 g air-dry soil, 2 mm mesh size, into a 250 ml polypropylene screw-cap centrifuge bottle/tube and add 100 ml acetic acid - 8-hydroxyquinoline reagent. Cap the tube and shake overnight (17 h) on a reciprocating shaker, at approximately 275 strokes of 25 mm length per minute at a constant temperature (20°C). Centrifuge for 15 min at 2800 rpm and remove an aliquot for the determination of acid extractable inorganic phosphorus (a). 

Ion chromatography (IC) offers the analytical tool for the determination of each of the inorganic acids in a single sample. The principle of ion chromatography is the separation and measurement of ions in solution using ion exchange resins, background suppression, and conductimetric detection (5). 

In the absence of a direct method of monitoring breakthrough for each of the inorganic acids, breakthrough was determined by analysis of the backup sections of the samplers. 

Sample Stability. The stability of inorganic acid samples on the silica gel collection tubes was determined by storing samples for a period of 10 days. Twelve 3-hour acid mist samples were generated at an air concentration equivalent to... 

This work has demonstrated that sorbent tubes are viable samplers for inorganic acid mists existing as vapors and aerosols. A silica gel sampling tube was developed which will collect at least a 4-hour sample of inorganic acid at a nominal flow rate of 0.2 Lpm. The optimum sampler geometry was determined to be a 7-mm O.D./4.8-mm I.D. glass tube packed with 20-40 mesh washed silica gel, 700 mg in the primary section and 200 mg in the backup. 

Airborne inorganic acids exist in the workplace environment as both vapors and particulates. To monitor for the common inorganic acids, a single, non-liquid sampling device to collect both vaporous and aerosol contaminants quantitatively, and an analytical method to determine these acids in a single sample was desired. 

Ion chromatography offers the analytical tool for the determination of inorganic acids in a single sample. In... 

The properties of Ge(OR)4 allow them to be considered more likely to be the esters of an inorganic acid than metal alkoxides these are colorless volatile liquids, containing monomeric tetrahedral molecules. The solid crystalline form is known only for R = Bu, OC6Hnc, and also 2,6-substituted phenoxides. All the members of the Ge(OR)4 homologous series are characterized by thoroughly determined physical characteristics — density, refraction index, surface tension, viscosity (and calculated parachor values), dipole moments in different solvents [222, 857, 1537] (Table 12.9). The results of the investigation of vapor pressure, density, viscosity polytherms, and so on. permitted rectification for the preparation of samples of high purity for sol-gel and MOCVD applications [682, 884]. 

Butler [3] determined inorganic arsenic species in non saline waters by ion exclusion chromatography with electrochemical detection. Two species were separated by ion exclusion chromatography using 0.10M orthophosphoric acid eluent. Arsenic(III) was detected by its oxidation at a platinum wire electrode. Measurement of total inorganic arsenic after reduction of arsenic(V) to arsenic(III) by sulphur dioxide enabled... 

The last equation is the Henderson-Hasselbalch equation. Its use will be demonstrated in the sections that follow. The ratio of A" to HA can be determined if the Ka and H+ values are fixed. It is the H+ concentration, therefore, that determines the net charge (ratio of charged to uncharged species). Conversely, the H+ can be determined if the PC to HA ratio is fixed. Table 1.18 lists various organic and inorganic acids of the monoprotic or polyprotic form along with their pKa values. Note that in the equations above and throughout this chapter, it is assumed that concentration equals activity. These two terms are discussed in detail in Chapter 2. 

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