Capacity of a solute

When small amounts of hydronium or hydroxide ions are added to a buffer solution, the pH changes are very small. There is a limit, however, to the amount of protection that a buffer solution can provide. After either buffering agent is consumed, the solution loses its ability to maintain near-constant pH. The buffer capacity of a solution is the amount of added H3 O or OH that the buffer solution can tolerate without exceeding a specified pH range. 

ANC of Humus. The acid neutralizing capacity of a solution containing humus is primarily due to the sum of concentrations of dissociated humus and of free OH ... 

The extent to which the pH of a solution is buffered against additions or removals of protons is measured by the solution s pH buffer capacity. This is defined as the amount of strong acid or base required to produce unit change in pH. The buffering depends on the transfer of protons between donors and acceptors, i.e. Bronsted acids and bases, which form conjugate acid-base pairs. The pH buffer capacity of a solution is calculated from the buffer capacities of the individual acid-base pairs present. 

Alkalinity—The capacity of a solution to neutralize any acid added to it. 

Acidity— The capacity of a solution to absorb the effect of the addition of a base. Alkalinity—The capacity of a solution to absorb the effect of the addition of an acid. 

Buffer capacity of a solution is defined as the number of moles of a strong acid (or a strong base) that causes 1.00 L of a buffer to undergo a 1.00-unit change in pH. 

Derive an equation for the buffer capacity of a solution due to its carbonate alkalinity at constant CO2 pressure. Base the calculation on the equation for total carbonate alkalinity (Cg), but do not convert that equation to the proton form before differentiation. This approach was suggested by van Breemen and Wielamaker (1974a 1974b). 

In general terms, alkalinity is the Acid Neutralizing Capacity of a solution, that is, the quantity of acid required to neutralize the solution. The acidity is similarly the Base Neutralizing Capacity , the quantity of base required to neutralize the acidity of a solution. Alkalinity and acidity are determined by titrating a sample of solution with an acid (such as HC1) or a base (such as NaOH) of known concentration. However, the variety of ways in which these simple concepts can be defined and interpreted has led to much confusion. Several modeling programs now do not allow input of acidity or alkalinity, as such, partly because of this confusion. However, others do, and in any case users will still have to deal with these concepts if they appear in their analyses. 

The third unusual property of aqueous solutions of inert gas molecules is the relatively large partial molar heat capacity of the solute in water. This is equivalent to a large heat capacity of the solvation of the inert gases in water. The partial molar heat capacity of a solute s in mixtures of s and water is defined by... 

It may be stated The absorptive capacity of a solution is directly proportional to the number of absorbing entities of the absorbing substance. 

Titration (chemical analysis) The determination of the reactive capacity of a solution, such as acidity or alkalinity, by adding another solution with a known composition, in known ratios, until a desired end point, such as color, is reached. 

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