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

Ideal Solutions or Mixtures01:20

Ideal Solutions or Mixtures

From a molecular perspective, an ideal solution is one in which the intermolecular interactions between unlike molecules are, on average, the same as those between like molecules. This is the case for ideal gas mixtures, where the molecules are far apart and do not interact with each other. However, for condensed phases like liquids or solids, the molecules are close together and interact with each other. In an ideal solution, the molecules of different species are so similar to each other that...
Nonideal Two-Component Liquid Solutions01:29

Nonideal Two-Component Liquid Solutions

Nonideal liquid solutions, also known as real solutions, do not strictly follow Raoult's law. Raoult's law is a rule of thumb in physical chemistry. However, not all mixtures adhere to this law due to varying molecular interactions. For example, in an acetone/chloroform solution, the individual vapor pressures of the components are lower than expected, resulting in a total vapor pressure below that predicted by Raoult's law, causing a negative deviation.On the other hand, in an ethanol/water...
Expressing Solution Concentration02:48

Expressing Solution Concentration

A solute is a component of a solution that is typically present at a much lower concentration than the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
Concentrations may be quantitatively assessed using a wide variety of measurement units, each convenient for particular applications. Molarity (M) is a useful concentration unit for many applications in chemistry.
¹H NMR: Complex Splitting01:13

¹H NMR: Complex Splitting

A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Ideal Solutions02:24

Ideal Solutions

According to Raoult’s law, the partial vapor pressure of a solvent in a solution is equal or identical to the vapor pressure of the pure solvent multiplied by its mole fraction in the solution. However, Raoult's Law is only valid for ideal solutions. For a solution to be ideal, the solvent-solute interaction must be just as strong as a solvent-solvent or solute-solute interaction. This suggests that both the solute and the solvent would use the same amount of energy to escape to the vapor phase...
Chemical and Solubility Equilibria02:21

Chemical and Solubility Equilibria

The free energy change associated with dissolving a solute in a liter of solvent is called the free energy of a solution, ΔGsolution. The overall ΔGsolution is expressed as the balance of ΔGinteraction against the always-favorable free-energy of mixing, ΔGmixing. Solution formation is favorable if  ΔGsolution is less than zero, whereas it is unfavorable if ΔGsolution is greater than zero. In short, for a solution to form and complete dissolution to take place, the Gibbs energy change must be...

You might also read

Related Articles

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

Sort by
Same author

Reshaping two-dimensional MoS<sub>2</sub> for superior magnesium-ion battery anodes.

Journal of colloid and interface science·2021
Same author

Effect of chemical aging of aqueous organic aerosols on the rate of their steady-state nucleation.

Physical chemistry chemical physics : PCCP·2020
Same author

Kinetic equation of concurrent nucleation and chemical aging of an ensemble of aqueous organic aerosols.

Physical review. E·2020
Same author

OH-Initiated Reactions of <i>para</i>-Coumaryl Alcohol Relevant to the Lignin Pyrolysis. Part III. Kinetics of H-Abstraction by H, OH, and CH<sub>3</sub> Radicals.

The journal of physical chemistry. A·2020
Same author

OH-Initiated Reactions of <i>para</i>-Coumaryl Alcohol Relevant to the Lignin Pyrolysis. Part II. Kinetic Analysis.

The journal of physical chemistry. A·2020
Same author

Bond Number Revisited: Axisymmetric Macroscopic Pendant Drop.

Langmuir : the ACS journal of surfaces and colloids·2020

Related Experiment Video

Updated: Jul 7, 2026

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels

Published on: September 8, 2016

Excess around a central molecule with application to binary mixtures.

Ivan L Shulgin1, Eli Ruckenstein

  • 1Department of Chemical & Biological Engineering, State University of New York at Buffalo, Amherst, NY 14260, USA. ishulgin@eng.buffalo.edu

Physical Chemistry Chemical Physics : PCCP
|February 14, 2008
PubMed
Summary
This summary is machine-generated.

A new formula accurately calculates molecular excess or deficit in binary mixtures, revealing preferential solvation. This goes beyond traditional methods using Kirkwood-Buff integrals by including inaccessible volume effects.

More Related Videos

Spatial Separation of Molecular Conformers and Clusters
10:37

Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Related Experiment Videos

Last Updated: Jul 7, 2026

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels

Published on: September 8, 2016

Spatial Separation of Molecular Conformers and Clusters
10:37

Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Area of Science:

  • Physical Chemistry
  • Thermodynamics
  • Statistical Mechanics

Background:

  • Traditional models for molecular excess/deficit in binary mixtures rely on molar concentration and Kirkwood-Buff integrals.
  • These models often fail to accurately represent the complex interactions and spatial arrangements of molecules.
  • An additional term accounting for volume inaccessible to certain molecules due to the presence of a central molecule is necessary for accurate calculations.

Purpose of the Study:

  • To introduce and apply a new expression for calculating the excess or deficit of species in binary mixtures.
  • To establish a simple criterion for identifying preferential solvation in binary systems.
  • To validate the new expression using various binary mixtures, including Lennard-Jones fluids and mixtures with varying intermolecular interactions.

Main Methods:

  • Application of a refined formula for molecular excess/deficit, incorporating an inaccessible volume term.
  • Analysis of binary Lennard-Jones fluids to compare the new expression with conventional methods.
  • Investigation of binary mixtures with weak (argon/krypton) and strong (alcohols/water) intermolecular interactions.

Main Results:

  • The conventional c(i)G(ij) method consistently shows deficits, while the new expression reveals both excesses and deficits, accurately reflecting species distribution.
  • For argon/krypton mixtures, the new method predicts excess argon and deficit krypton, aligning with their molecular sizes.
  • In alcohol/water mixtures, the new expression accurately predicts significant excess of alcohols around central alcohol molecules and water around central water molecules, correlating with experimental observations of molecular clustering.

Conclusions:

  • The newly developed expression, which includes inaccessible volume, provides a more accurate description of molecular distribution in binary mixtures than traditional methods.
  • This refined approach offers a straightforward criterion for determining preferential solvation.
  • The findings have significant implications for understanding molecular clustering and solvation in complex liquid mixtures, particularly in alcohol-water systems.