Related Experiment Video
Updated: Jun 19, 2026
07:57
Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
Influence of surfactants on the force between two bubbles
1Particulate Fluids Processing Centre, Department of Mathematics and Statistics, The University of Melbourne, Parkville, Victoria 3010, Australia. O.Manor@ms.unimelb.edu.au
Langmuir : the ACS Journal of Surfaces and Colloids
|October 9, 2009
Summary
Surface-active species slow down bubble collisions, impacting emulsion stability. Simple measures quantify this effect, aiding experimental design without complex simulations.
Area of Science:
- Colloid and Surface Science
- Fluid Dynamics
- Materials Science
Background:
- Bubble collisions are fundamental to multiphase systems.
- Interfacial velocity retardation by surface-active species influences dynamic forces.
- Understanding these interactions is crucial for emulsion stability.
Purpose of the Study:
- To derive simple measures quantifying surface-active species influence on bubble collisions.
- To provide guidelines for designing and analyzing emulsion stability experiments.
- To characterize interfacial dynamics without numerical analysis.
Main Methods:
- Derivation of quantitative measures from a theoretical model.
- Validation of the theoretical model against experimental data.
- Analysis of surface mobility variations with film geometry.
Main Results:
- Simple measures effectively quantify the impact of surface-active species.
- The derived measures characterize interfacial dynamics without numerical analysis.
- Surface mobility can vary with film geometry, but small surfactant amounts often suffice for interface immobilization.
Conclusions:
- The study provides practical tools for assessing bubble collision dynamics.
- Findings simplify the analysis of emulsion stability and related phenomena.
- Effective interface immobilization can be achieved with minimal surface-active species.
Related Concept Videos
01:13Excess Pressure Inside a Drop and a Bubble
The shape of a small drop of liquid can be considered spherical, neglecting the effect of gravity. This drop can further be considered as two equal hemispherical drops put together due to surface tension. The forces acting on the spherical drop are due to the pressure of the liquid inside the drop, the pressure due to air outside the drop, and the force due to the surface tension acting on the two hemispherical drops.
01:27Surface Active Agents
Surfactants, named for their behavior at interfaces, positively adsorb at the interfaces of two phases, reducing interfacial tension. Their versatility as emulsifiers, detergents, and foaming agents stems from this ability. Surfactants, often termed amphiphiles, share the property of amphipathy, with molecules having both hydrophilic and hydrophobic portions. The hydrophilic part is called the head, and the hydrophobic part, including an elongated alkyl substituent, forms the tail.Surfactants...
02:57Surface Tension, Capillary Action, and Viscosity
Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
01:22Surface Tension of Fluid
Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies with...
Surface tension varies with...
01:16Surface Tension and Surface Energy
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
01:30Micelles
Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...