surface-active agent

Học thuật
Thân thiện
surface-active agent

A scientist adds a surface-active agent to a beaker of water.

Definition

Noun: A substance that lowers the surface tension of a liquid it is dissolved in or the interfacial tension between two liquids, or between a liquid and a solid. This property allows the agent to act as a detergent, emulsifier, wetting agent, or foaming agent.

Usage

A surface-active agent is used to alter the properties at the interface between different phases (e.g., liquid-air, liquid-liquid, liquid-solid). Its molecules have a structure with both water-attracting (hydrophilic) and water-repelling (hydrophobic) parts.

Examples
  • Noun:
    • Soap is a common surface-active agent that helps remove grease from dishes.
    • The formulation includes a surface-active agent to ensure the spray evenly coats the plant leaves.
    • Researchers are developing a biodegradable surface-active agent for industrial cleaning.
Advanced Usage
  • Critical Micelle Concentration (CMC): This is the specific concentration at which molecules of a surface-active agent begin to form micelles (aggregates) in a solution, a key property in its effectiveness.
    • The cleaning power increases significantly once the concentration of the surface-active agent exceeds its Critical Micelle Concentration.
Variants and Related Words
  • Surfactant (n): A common synonym and shortened form of "surface-active agent."
    • This shampoo contains a mild surfactant derived from coconut oil.
  • Detergent (n): A cleaning agent that is typically a surface-active agent.
  • Emulsifier (n): A type of surface-active agent that helps mix two immiscible liquids, like oil and water.
Synonyms
  • Surfactant
  • Wetting agent
  • Emulsifier (when used for that specific function)
Related Phrases and Technical Terms
  • To act as a surfactant: To function as a surface-active agent.
    • This compound can act as a surfactant in aqueous solutions.
  • Surface activity: The phenomenon or measure of a substance's effectiveness as a surface-active agent.
    • The surface activity of the new formulation was tested in the lab.
surface-active agent

A scientist adds a surface-active agent to a beaker of water.

Noun
  1. a chemical agent capable of reducing the surface tension of a liquid in which it is dissolved