Conjugate acid/base

C18-0095. The pH of a formic acid/formate buffer solution is 4.04. Calculate the acid/conjugate base ratio for this solution. Draw a molecular picture that shows a small region of the buffer solution. (You may omit spectator ions and water molecules.) Use the following symbols ... 

Define buffer solution, conjugate acid, conjugate base, conjugate acid-base pair, buffer capacity, and buffer region. 

A buffer solution of pH 3.00 is needed. From Table 5.1, select a weak acid-conjugate base combination that would give that pH and calculate the ratio of acid concentration to conjugate base concentration that would give that pH. 

Buffer solutions have two important characteristics. One of these characteristics is the pH of the solution. The other is its buffer capacity the amount of acid or base that can be added before considerable change occurs to the pH. The buffer capacity depends on the concentration of the acid/conjugate base (or the base/conjugate acid) in the buffer solution. When the ratio of the concentration of the buffer components is close to 1, the buffer capacity has reached its maximum. As well, a buffer that is more concentrated resists changes to pH more than than a buffer that is more dilute. This idea is illustrated in Figure 8.10, with buffer solutions of acetic acid and acetate of different concentrations. 

Recall, from Chapter 8, that a buffer consists of a weak acid/conjugate base mixture or a weak base/conjugate acid mixture. One buffer that you examined previously contains acetic acid and sodium acetate. The common-ion effect applies to this buffer. The equilibrium of the acetic acid is affected by the common acetate ion from sodium acetate. 

Acid Base Conjugate acid Conjugate base... 

Conjugate Acid-Base Pair in the Bronsted theory, an acid and its conjugate base or a base and its conjugate acid Conjugate Base in the Bronsted theory, the substance that remains when an acid donates a proton... 

Base) (Acid) (Conjugate acid) (Conjugate base)... 

Polarization of the solvent medium rather than that of the acid-conjugate base pair better explains the observed influence of fluorination on acidity in solution. These interactions can be attributed to the dipole-mediated assistance to solvent organization.33... 

However, the conjugate acid-conjugate base nomenclature is convenient, and we shall continue to use it. 

In order to avoid proliferation of tables, it iscus tomary to report only one constant for each conjugate acid-conjugate base pair. The reader may easily verify thatif acid A is a stroneer acid an H B. the conjugate base of A will be a weaker base than the conjugal nf R—... 

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