Monoprotic acids, defined

In many experimental situations, one controls the total analytical concentration, C, i.e., the sum of the concentrations of the various possible forms present. For example, we may weigh a certain amount of acetic acid and/or sodium acetate, and dissolve it in a given amount of water, in which case we know the total analytical concentration C = [HAc] + [Ac ]. In situations like that it is often useful to define the concentration fraction of a particular species in the mixture. For the simple monoprotic acid defined in (4.1-3) we have... 

Define monoprotic acid, polyprotic acid, monobasic base, polybasic base, titration curve, and inflection point. 

A dimensionless parameter (usually symbolized as a) indicating the fraction of monoprotic acid present as its dissociated form. This parameter can be defined quantitatively as follows ... 

Obviously the buffer intensity can be expressed numerically by differentiating the equation defining the titration curve with respect to pH. For a monoprotic acid-base system (see equations 67 and 69). 

In an aqueous monoprotic acid-base system, [ANC] is defined by the right-hand side of equation 67 or 69 in Section 3.8. 

In the same monoprotic acid-base system, the base-neutralizing capacity with respect to the reference level (/ = 1) of a NaA solution (proton condition [HA] -I- [H ] = [OH ]) is defined by... 

Thus, the two equations (8) and (9) are sufficient to describe the entire pH solubility profile of a monoprotic acid, and the point of intersection is defined by equation (11) ... 

Dividing both sides of the equation by d[B] gives the reverse of equation (1.3), defining the buffer capacity. Equations (1.2) and (1.3) have been defined for monoproteic acids, but are also applicable as an initial approximation to di-acids, such as tartaric and malic acids. 

A salt is defined as a compound formed when the hydrogen of an acid is completely or partially replaced by a metal (Table 18.4). If all the hydrogen is replaced, a normal salt is formed if the hydrogen is not completely replaced, then an acidic salt is formed. Acid salts can only be formed by diprotic and triprotic acids monoprotic acids can only form normal salts. 

A search [10] of the World Drug Index revealed that 62.5% of marketed drugs are ionizable, which implies that these substances can exist in various charged states depending on the pH of the media. For ionizable drugs, solubility is pH dependent, and it is therefore important to understand the solubility in the context of pH. Ionization of a compound can be defined by the acid dissociation constant, p/C,. For the case of monoprotic compounds, the solubility at a given pH can be described by the following equations ... 

The extent of this dissociation is governed by its acid dissociation constant, Ka, and is defined for the case of a monoprotic weak acid, HL, as follows ... 

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