Accedi

For an ideal solution, the pH is defined as the negative logarithm of the hydrogen ion concentration. For a non-ideal solution, an accurate measurement of the pH must consider the negative logarithm of the hydrogen ion activity rather than concentration. In such a solution, the pH can be more accurately defined as the negative logarithm of a product of the hydrogen ion concentration and its activity coefficient.

In solutions of very low ionic strength—for example, pure water—the activity coefficient of the hydrogen ion is close to one when the ionic strength of the solution increases due to the addition of an electrolyte that does not donate or accept a proton. This results in a slight decrease in the pH of the solution. In other words, the addition of an electrolyte increases the hydrogen ion activity, or the effective hydrogen ion concentration in the solution, which decreases the pH of the solution.

Tags
Acid base EquilibriaPH DefinitionHydrogen Ion ConcentrationHydrogen Ion ActivityNon ideal SolutionActivity CoefficientIonic StrengthElectrolyte EffectsEffective Hydrogen Ion Concentration

Dal capitolo 2:

article

Now Playing

2.8 : Acid–Base Equilibria: Activity-Based Definition of pH

Chemical Equilibria

486 Visualizzazioni

article

2.1 : Ionic Strength: Overview

Chemical Equilibria

1.1K Visualizzazioni

article

2.2 : Ionic Strength: Effects on Chemical Equilibria

Chemical Equilibria

1.2K Visualizzazioni

article

2.3 : Thermodynamics: Chemical Potential and Activity

Chemical Equilibria

763 Visualizzazioni

article

2.4 : Thermodynamics: Activity Coefficient

Chemical Equilibria

1.1K Visualizzazioni

article

2.5 : Chemical Equilibria: Redefining Equilibrium Constant

Chemical Equilibria

472 Visualizzazioni

article

2.6 : Factors Affecting Activity Coefficient

Chemical Equilibria

646 Visualizzazioni

article

2.7 : Chemical Equilibria: Systematic Approach to Equilibrium Calculations

Chemical Equilibria

555 Visualizzazioni

article

2.9 : Ladder Diagrams: Acid–Base Equilibria

Chemical Equilibria

391 Visualizzazioni

article

2.10 : Ladder Diagrams: Redox Equilibria

Chemical Equilibria

393 Visualizzazioni

article

2.11 : Ladder Diagrams: Complexation Equilibria

Chemical Equilibria

286 Visualizzazioni

article

2.12 : Solubility Equilibria: Overview

Chemical Equilibria

511 Visualizzazioni

article

2.13 : Solubility Equilibria: Ionic Product of Water

Chemical Equilibria

880 Visualizzazioni

article

2.14 : Complexation Equilibria: Overview

Chemical Equilibria

529 Visualizzazioni

article

2.15 : Complexation Equilibria: The Chelate Effect

Chemical Equilibria

379 Visualizzazioni

See More

JoVE Logo

Riservatezza

Condizioni di utilizzo

Politiche

Ricerca

Didattica

CHI SIAMO

Copyright © 2025 MyJoVE Corporation. Tutti i diritti riservati