Film tension

{
  "id": "MLC-T-CHM-004423",
  "term": "Film tension",
  "field": "Chemistry",
  "definition": "The contractile force per unit length that a thin liquid film exerts on its surroundings, such as on the frame holding a soap film. It equals twice the surface tension of the liquid, one for each face, plus a correction for the interaction between the two interfaces, which matters only when the film is very thin. In a thick film that interaction term vanishes, and the film tension reduces to twice the surface tension.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "equilibrium film"
  ],
  "references": [
    "PAC, 1972, 31, 577. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry' on page 614 (https://doi.org/10.1351/pac197231040577)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/film-tension/"
}