Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Titration in Nonaqueous Solvents01:16

Titration in Nonaqueous Solvents

Most acid-base titrations are performed in an aqueous medium. In aqueous titrations, water competes with weaker acids or bases for proton donation or acceptance, leading to ambiguous endpoints in the titration curve. Water also affects the partial ionization of weak acids or bases. For example, water accepts a proton from acetic acid to form hydronium and acetate ions. The hydronium ion formed is a stronger acid than acetic acid, and the acetate ion is a stronger base than water. As a result,...
Relative Strengths of Conjugate Acid-Base Pairs02:29

Relative Strengths of Conjugate Acid-Base Pairs

Brønsted-Lowry acid-base chemistry is the transfer of protons; thus, logic suggests a relation between the relative strengths of conjugate acid-base pairs. The strength of an acid or base is quantified in its ionization constant, Ka or Kb, which represents the extent of the acid or base ionization reaction. For the conjugate acid-base pair HA / A−, the ionization equilibrium equations and ionization constant expressions are
Leveling Effect and Non-Aqueous Acid-Base Solutions02:11

Leveling Effect and Non-Aqueous Acid-Base Solutions

This lesson defines the leveling effect in acidic and basic solutions and its role in aqueous and non-aqueous solutions. It is essential to understand the competing nature of various species in a chemical system.
The Leveling Effect of a Solvent
A generic acid (HA) reacts with the generic base (B-) to yield the corresponding conjugate base (A-) and conjugate acid (HB):
Titration of a Weak Acid with a Weak Base01:08

Titration of a Weak Acid with a Weak Base

Weak acids and bases do not undergo dissociation completely, and titrations between these two are rarely studied. When such studies are performed, say, for the titration of a weak acid with a weak base, the titration curve plots the change in pH as a function of the volume of base added. Take the titration of acetic acid with ammonia, for instance. During the titration, these two species form ammonium acetate and water, but the pH change is slow and gradual.
As a result, there is no simple...
Position of Equilibrium in Acid-Base Reactions02:05

Position of Equilibrium in Acid-Base Reactions

In any solution, the value of pKa indicates whether an acid is completely dissociated or not. A negative pKa corresponds to a stronger acid, whereas a positive pKa corresponds to a weaker acid. Consider the reaction between ammonia and an ethoxide ion. In this reaction, ethanol with a pKa of 15.9 is a stronger acid than ammonia with a pKa of 38. Recall that the strong acid forms a weak conjugate base, and a weak acid forms a strong conjugate base. Hence, the ethoxide ion is a weak base.
Titration of a Weak Acid with a Strong Base01:30

Titration of a Weak Acid with a Strong Base

In titrating a weak acid with a strong base, different calculation methods are applied at various stages. Initially, the pH of a weak acid like acetic acid is calculated using its dissociation constant (Ka) and an ICE table. Upon addition of a strong base such as sodium hydroxide, a buffer forms, and its pH is determined using the Henderson-Hasselbalch equation. As more base is added and the titration reaches the halfway point, the pH becomes equal to the pKa of the acid, indicating equal...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Assessing Excessive Keratinization in Acral Areas through Dermatoscopy with Cross-Polarization and Parallel-Polarization: A Dermatoscopic Keratinization Scale.

Journal of clinical medicine·2023
Same author

Dual Piperidine-Based Histamine H<sub>3</sub> and Sigma-1 Receptor Ligands in the Treatment of Nociceptive and Neuropathic Pain.

Journal of medicinal chemistry·2023
Same author

Rationally designed N-phenylsulfonylindoles as a tool for the analysis of the non-basic 5-HT<sub>6</sub>R ligands binding mode.

European journal of medicinal chemistry·2020
Same author

Synthesis, structure and biological activity of four new picolinohydrazonamide derivatives.

Acta crystallographica. Section C, Structural chemistry·2020
Same author

4-Substituted picolinohydrazonamides as a new class of potential antitubercular agents.

European journal of medicinal chemistry·2020
Same author

2-Aminoimidazole-based antagonists of the 5-HT<sub>6</sub> receptor - A new concept in aminergic GPCR ligand design.

European journal of medicinal chemistry·2019

Related Experiment Video

Updated: Jun 17, 2026

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems
05:46

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

Published on: January 24, 2014

Modelling of acid-base equilibria in binary-solvent systems: A comparative study.

Bogusław Pilarski1, Agnieszka Dobkowska, Henryk Foks

  • 1P.P.H.U. Cerko s.c., 80 299 Gdańsk, Afrodyty 9, Poland.

Talanta
|December 17, 2009
PubMed
Summary

This study introduces a new pH titration modeling approach for hydro-organic acid-base systems. The method accurately determines acidity parameters (pK) for weak acids in mixed water-organic solvent solutions.

More Related Videos

Preparation of Binary and Ternary Deep Eutectic Systems
06:15

Preparation of Binary and Ternary Deep Eutectic Systems

Published on: October 31, 2019

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments
13:05

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments

Published on: January 23, 2018

Related Experiment Videos

Last Updated: Jun 17, 2026

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems
05:46

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

Published on: January 24, 2014

Preparation of Binary and Ternary Deep Eutectic Systems
06:15

Preparation of Binary and Ternary Deep Eutectic Systems

Published on: October 31, 2019

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments
13:05

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments

Published on: January 23, 2018

Area of Science:

  • Analytical Chemistry
  • Physical Chemistry
  • Physical Organic Chemistry

Background:

  • Accurate determination of acid-base properties is crucial in various chemical applications.
  • Modelling acid-base equilibria in mixed solvent systems presents unique challenges.
  • Existing methods may not fully capture the complex interactions in hydro-organic media.

Purpose of the Study:

  • To develop a novel modeling approach for binary hydro-organic acid-base systems.
  • To determine acidity parameters (pK) for weak acids (HL) in water-organic solvent mixtures.
  • To establish relationships between pK and solvent composition (mole fraction of B).

Main Methods:

  • pH titrations were performed in binary hydro-organic systems (H2O+B).
  • A new modeling strategy was applied to analyze titration data.
  • The Redlich-Kister equation and Legendre functions with orthogonal polynomials were utilized.

Main Results:

  • The proposed models successfully determined pK values for weak acids.
  • Established pK = pK(x) relationships, where x is the mole fraction of the organic co-solvent B.
  • Successfully determined pK(B) = pK(1) for weak acids in pure organic solvent B.

Conclusions:

  • The new modeling approach is effective for analyzing acid-base systems with organic co-solvents.
  • The Redlich-Kister equation and Legendre functions are suitable tools for this modeling.
  • This method provides a reliable way to determine acid dissociation constants in mixed solvents.