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Acidity-alkalinity

There are two kinds of acidity or alkalinity components in natural systems (1) acidity or alkalinity dissolved in water, and (2) acidity or alkalinity present in the solid phase. The solid-phase acidity or alkalinity represents the reservoir of acidity or alkalinity encountered in water. By definition (commonly employed by commercial analytical [Pg.82]


Hydrolysis of Acetanilide. Anilides in general, such as acetanilide and benzanilide (p. 245), may be hydrolysed by caustic alkalis or by acids. Alkaline hydrolysis, however, is usually very slow, and therefore... [Pg.108]

Benzoyl compounds are readily hydrolysed by heating with about 70 per cent, sulphuric acid (alkaline hydrolysis is very slow for anilides) ... [Pg.582]

Composition of Indicator Solution p/ Acid Alkaline Notes... [Pg.945]

Highly acidic/alkaline moieties may also cause permanent chemical alterations in the adsorbent (aluminas are sensitive to acid solutions, siUca gels are stre —12 range. [Pg.458]

ASTM has estabhshed standard test methods to determine acid acceptance, acidity, alkalinity, color, corrosivity to metals, nonvolatile matter content. [Pg.29]

Hydrolysis. The lactone is easily hydroly2ed by alkaUes to the corresponding salts of coumarinic acid or o-hydroxy-i j -cinnamic acid [495-79 ]. Coumarinic acid salts are odorless. Coumarinic acid and salts revert to coumarin upon acidification with inorganic acids. Alkaline fusion of coumarin yields salts of sahcyhc and acetic acids. [Pg.320]

Upset An upset digester does not decompose organic matter properly. The digester is characterized by low gas production, high volatile acid/alkalinity relationship, and poor liquid-solids separation. A digester in an upset condition is sometimes called a "sour" or "stuck" digester. [Pg.627]

Alkali salts of the carboxylic acids Alkaline pH range Acidic pH range... [Pg.198]

Nickel is usually alloyed with elements including copper, chromium, molybdenum and then for strengthening and to improve corrosion resistance for specific applications. Nickel-copper alloys (and copper-nickel alloys see Section 53.5.4) are widely used for handling water. Pumps and valve bodies for fresh water, seawater and mildly acidic alkaline conditions are made from cast Ni-30% Cu type alloys. The wrought material is used for shafts and stems. In seawater contaminated with sulfide, these alloys are subject to pitting and corrosion fatigue. Ammonia contamination creates corrosion problems as for commercially pure nickel. [Pg.906]

Reactions with aqueous solutions. Uniform dissolution or corrosion of metals in acid, alkaline or neutral solutions (e.g. dissolution of zinc in hydrochloric acid or in caustic soda solution general corrosion of zinc in water or during atmospheric exposure). Reactions with non-aqueous solution (e.g. dissolution of copper in a solution of ammonium acetate and bromine in alcohol). [Pg.20]

Too low pH either overall or in acid spots in the event of poor microhomogenization of the acid alkaline phase should be avoided to prevent hydrolysis of the organic acid product to alcohol (alcohol ether) and sulfuric acid, which will catalyze further hydrolysis ... [Pg.669]

Liquid-liquid extraction (also called solvent extraction) is the transfer of a substance (a consolute) dissolved in one liquid to a second liquid (the solvent) that is immiscible with the first liquid or miscible to a very limited degree. This operation is commonly used in fine chemicals manufacture (I) to wash out impurities from a contaminated solution to a solvent in order to obtain a pure solution (raffinate) from which the pure substance will be isolated, and (2) to pull out a desired substance from a contaminated liquid into the solvent leaving impurities in the first liquid. The former operation is typically employed when an organic phase is to be depleted from impurities which are soluble in acidic, alkaline, or neutral aqueous solutions Water or a diluted aqueous solution is then used as the solvent. The pure raffinate is then appropriately processed (e.g. by distillation) to isolate the desired consolute. In the latter version of extraction impurities remain in the first phase. The extract that has become rich in the desired consolute is then appropriately processed to isolate the consolute. Extraction can also be used to fractionate multiple consolutes. [Pg.252]

When the water is too alkaline, swimmers experience similar physical discomfort—burning eyes and nose and itchy, dry skin. The effect on the pool, however, is different. When water is alkaline, calcium dissolved in the pool water can precipitate (fall) out of solution. A precipitate is a solid that forms from a solution due to a chemical reaction. This solid creates unsightly scales on the sides of the pool. Like water that is too acidic, alkaline water also affects the efficiency of the chlorine. More chlorine needs to be added to alkaline water to effectively disinfect the pool. Over time, a swimming pool that is not kept at a neutral pH can become very expensive to maintain. [Pg.48]

The pH of Soils. The pH of soils (see Textbox 48) varies widely with location and climate the local climate of a region usually provides a clue as to the pH of the soil. In high-rainfall regions, for example, soils are generally acid. Alkaline soils, in contrast, typically occur in low-rainfall areas the actual value of the pH varies over a wide range, from below 5 in very acid... [Pg.247]

All add solutions taste sour and are more or less corrosive and chemically quite reactive they react with most metals, many of which are corroded and dissolved by acids. Alkaline solutions, also chemically reactive, are caustic (they burn or corrode organic tissues), taste bitter, and feel slippery to the touch. Both acids and bases change the color of indicators (substances that change color, hue, or shade depending on whether they are in an acid or basic environment). [Pg.249]

Acids, alkalines, other corrosives many are highly mobile in soil. [Pg.45]

Hacias KJ, Cormier GJ, Nourie SM, Kubel EJ (1997) Guide to acid, alkaline, emulsion, and ultrasonic cleaning. ASM International, Materials Park... [Pg.28]

As a safer alternative to digestion of vegetable matter with perchloric acid, alkaline oxidation of sulfur compounds to sulfate by sodium hypobromite, and reduction of sulfate to hydrogen sulfide by hydriodic acid/formaldehyde/phosphinic acid is recommended. [Pg.1364]

Cation-selective ionophores are the most successful in polymeric ISEs and selectivi-ties exceeding ten orders of magnitude became quite common. The cation-ionophore binding occurs dominantly due to Lewis interactions and could be understood in terms of hard and soft acid and bases theory (HSAB). While hard base oxygen atoms originate from ester, ether or carbonyl functionalities, and interact with hard acid alkaline cations, the softer sulfur or nitrogen atoms better bind with transition metal ions. Cation... [Pg.121]

Acidity/ Alkalinity Refrigeration Gains or losses of C02 affect the result. Microbial action can affect this, should be one of the first analyses of the sample. [Pg.41]


See other pages where Acidity-alkalinity is mentioned: [Pg.86]    [Pg.468]    [Pg.221]    [Pg.69]    [Pg.352]    [Pg.304]    [Pg.163]    [Pg.177]    [Pg.111]    [Pg.148]    [Pg.165]    [Pg.2461]    [Pg.129]    [Pg.55]    [Pg.184]    [Pg.906]    [Pg.21]    [Pg.751]    [Pg.243]    [Pg.490]    [Pg.101]    [Pg.1362]    [Pg.93]    [Pg.94]    [Pg.248]    [Pg.389]    [Pg.65]    [Pg.309]    [Pg.309]    [Pg.309]   
See also in sourсe #XX -- [ Pg.21 ]




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