Acid-base balance concepts

The Lux-Flood theory relates to oxide melts. Geologists have often used acid-base concepts for the empirical classification of igneous silicate rocks (Read, 1948). Silica is implicitly assumed to be responsible for acidity, and the silica content of a rock is used as a measure of its acid-base balance ... 

Fluids and Electrolytes Demystified is a detailed overview of the critical concepts involved in fluid, electrolyte, and acid-base balance and imbalance, collectively one of the hardest topics to master in undergraduate nursing. Fluid and electrolyte balance and acid-base balance have challenged students for ages. Some of the difficulty in understanding this content may lie in the attempt to remember each individual detail or symptom associated with an imbalance combined with the difficulty of mastering the physiology involved in each process. The list of symptoms of imbalance can be extensive there is often duplication and overlap between electrolyte and acid-base imbalances. In Fluids and Electrolytes Demystified, the normal functions are discussed to provide baseline data. The concepts of imbalance are presented individually, but the links between concepts are addressed. The reader is led toward two facts that many of the fluid, electrolyte, and acid-base imbalance symptoms are interrelated and that the imbalances themselves are interlinked. 

Fluids and Electrolytes Demystified is a detailed, easy-to-understand overview of the concepts it focuses on the information that students need most to understand the conditions that result in fluid and electrolyte imbalances. The book emphasizes the most critical information in fluids and electrolytes by discussing the underlying mechanisms involved in maintaining fluid, electrolyte, and acid-base balance and by discussing the factors that fail and result in an imbalance. 

Fluids and Electrolytes Demystified is designed to make the concepts associated with fluid, electrolyte, and acid-base balance and imbalance clear and understandable. The key to demystifying the concepts is to see the connections and to make sense of the underlying processes involved, which will lead to an understanding of the imbalances that occur when normal processes fail. 

In earlier sections of this chapter, we showed how to write and balance equations for precipitation reactions (Section 4.2) and acid-base reactions (Section 4.3). In this section we will concentrate on balancing redox equations, given the identity of reactants and products. To do that, it is convenient to introduce a new concept, oxidation number. 

Fundamental Concepts of Acid-Base and Oxidation-Reduction Balances... 

Ionic fluorides such as KP behave as bases in Brp3, whereas some covalent fluorides such as Sbp5 behave as acids. On the basis of the solvent system concept, write balanced chemical equations for these acid-base reactions of fluorides with Brp3. 

The causes of acid-base disorders, resulting laboratory values, and compensatory responses are discussed here in the traditional categorization of these disorders. However, it is often difficult to remember which disorders fall into which categories, so it is common for mnemonic devices or tables to be used to facilitate description of these disorders. A useful and more logical approach is to reaUze tliat an acidosis can only occur as a result of one (or a combination) of three mechanisms (1) increased addition of acid, (2) decreased elimination of acid, and (3) increased loss of base. Similariy, alkalosis occurs only by (1) increased addition of base, (2) decreased ehmination of base, and (3) increased loss of acid. Dufour has illustrated this simple concept by depicting the body as a two-tank vat, one of acid and one of base, with inputs and outputs for each vat (Figure 46-13). In the normal setting, these inputs and outputs are balanced an acid-base disorder then involves a perturbation in the input or output of these body reservoirs, as discussed in the next section. 

Our principal interest in acid-base chemistry is in aqueous solutions, where the Br0nsted-Lowry theory prevails. The balance of this chapter is limited to the proton-transfer concept of acids and bases. 

Finally, we complete the discussion on polymer adsorption with the Lewis acid-base concept, which is a useful tool for evaluating the relative adsorption of polymers versus solvents on the same solid surface (Figure 7.11). The relative interactions of polymer-solid, polymer-solvent and solvent-solid must be accounted for in the case of adsorption of polymers from solutions on solids. It is important at first to know whether these compounds (sohd surface, solvent, polymer) have an acidic or basic character. Notice (Figure 7.11) that very acid solvents compete (with the acidic surface) for the basic polymer and very basic solvents compete (with the basic polymer) for the acidic surface. It seems that in many cases, solvents of balanced acidity/basicity (i.e. not very acid, not very basic, almost neutral) are the best choices for accomplishing maximum adsorption. 

Water Flux in Polymer Electrolyte Membranes Water flux in the solid electrolyte membrane of the PEFC must be understood to grasp the concept of a local water balance in the fuel cell. From Chapter 5, we know that the ionic conductivity of perfluorosulfonic acid-based solid polymer electrolytes is a strong function of water content. Within the electrolyte, there are four basic modes of transport, as schematically illustrated in Figure 6.21 ... 

This is based on a shift in the concept of neutralization , from the complete disappearance of properties characteristic of acids and bases, to the achievement of an exact balance between the number of moles of acid and the equivalent number of moles of base. For the reaction between hydroehlorie acid and sodium hydroxide mentioned in the previous section, the neutral point and the equivalence point are the same, but for the reaction between acetic acid and sodium hydroxide, they are not. 

The past 10 to 20 years have seen the accumulation of an increasing volume of sound biological, biochemical, and biomedical evidence on the diverse actions of ascorbic acid/vitamin C. Throughout the book the terms ascorbic acid and vitamin C will be used freely and interchangeably, without abbreviation, at the discretion of the different authors. Although the somewhat speculative orthomolecular concepts for ascorbic acid action advanced by Linus Pauling were not entirely based on hard scientific facts, we can now see from the balanced information presented in this book that, in at least some instances, his ideas may have been farsighted. 

In total, a corrosive is not exclusively an acid or a base. Other molecular reactive functions can develop, as we have just seen, an aggressive character toward the skin. A corrosive is not a substance only soluble in water as is the case of fatty amines or with some fatty acids, for example. This type of molecules can also present an amphiphilic character. One pole is hydrophilic and the other lipophilic. These properties are useful to classify the behavior and the effectiveness of emulsifiers. This is the concept of hydrophilicity/lipophilicity balance (HLB). The more the value is high (scale from 1 to 40), the more the emulsifier is hydrophilic. These concepts are also used to justify suitable and efficient conditions of washing skin splashes. 

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