colloidal suspension
Học thuậtThân thiện
Definition
Noun: A colloidal suspension is a specific type of mixture where solid particles are dispersed and suspended within a continuous liquid phase. The solid particles are typically very small (between 1 nanometer and 1 micrometer in size) and do not settle out quickly due to gravity. This stability distinguishes it from a regular suspension where particles eventually settle.
Usage and Examples
- General Use: The term is used in scientific contexts to describe a stable, heterogeneous mixture.
- Milk is a common example of a colloidal suspension where fat globules are dispersed in water.
- The chemist prepared a colloidal suspension of gold nanoparticles for the experiment.
Advanced Usage
- Technical Context: In materials science and chemistry, a colloidal suspension is a system where the dispersed solid phase (the ) and the liquid (the or ) are in different states of matter.
- The stability of the colloidal suspension is maintained by electrostatic repulsion between the particles.
Variants and Related Words
- Colloid (n): The broader category of mixtures that includes colloidal suspensions, as well as other combinations like aerosols (solid/liquid in gas) or foams (gas in liquid/solid).
- Colloidal Solution (n): Often used interchangeably with "colloidal suspension," though some scientific distinctions exist based on particle size and interaction with the medium.
- Suspension (n): A more general mixture where solid particles are mixed with a liquid but may settle over time (e.g., muddy water).
Synonyms
- Colloidal dispersion: A synonym emphasizing the act of dispersing particles.
- Sol: A specific type of colloidal suspension where solid particles are in a liquid.
Related Phrases and Terms
- Tyndall effect: The scattering of light by particles in a colloidal suspension, which makes a beam of light visible through the mixture. This is a key identifying property.
- The Tyndall effect is clearly observed when a laser pointer shines through a colloidal suspension.
Noun
- a colloid that has a continuous liquid phase in which a solid is suspended in a liquid