A substance (as albumin, gum, gelatin, etc.) which is of a gelatinous rather than a crystalline nature, and which diffuses itself through animal membranes or vegetable parchment more slowly than crystalloids do; -- opposed to crystalloid.
a substance consisting of particles that are dispersed throughout another substance and are too small for resolution with an ordinary light microscope but are incapable of passing through a semipermeable membrane : a mixture (as smoke) consisting of a colloid together with the medium in which it is dispersed
Colloidal particles are so small and light that they do not settle in water. The movement of water molecules is enough to keep them in suspension. It is important to remember that colloidal particles occur in a suspension, not a solution. A simple way to tell the difference is to shine a beam of light through the liquid. If you can see the beam it is a suspension.
Physical Chemistry. A substance consisting of very tiny particles that are usually between 1 nanometer and 1000 nanometers in diameter and that are suspended in a continuous medium, such as a liquid, a solid, or a gaseous substance. the translucent, pale yellow, gelatinous substance resulting from colloid degeneration.
Colloid is a group of small particles that form a mass unit. The term "colloid" is used when we talk about soil particles. The unit of soil that has many particles can be through of as a colloid unit that has properties of electric charge and mass (weight). Clay colloids are very small particles of soil bound together ("glued") by organic matter. Clay colloids have many cation exchange sites (negatively charged sites) that can hold onto cations like potassium, copper and calcium.
mixture containing particles that are intermediate in size between those of a suspension and a true solution; these particles are evenly distributed throughout the liquid and do not settle out with time; the particles are large enough to cause the Tyndall effect; a dispersion of particles from 1 to 100 nm in at least on dimension, in a continuous medium.
a suspension in which the dispersed phase is so small that gravitational forces are negligible and interactions are dominated by short-range forces, such as Van der Waals attraction and surface charges
Usually refers to the state of subdivision of dispersed particles; intermediate between very small particles in true solution and large particles in suspension. Proteins and pectins are usually colloidal.
A substance composed of extremely small particles, ranging from 0.2 micron to 0.005 micron which when mixed with a liquid will not gravity separate or settle, but remain permanently suspended in solution.
Any gas, solid, or liquid in a fine state of subdivision, with particles too small to be visible in an ordinary optical microscope, that is dispersed in a continuous gaseous, liquid, or solid medium and does not settle or settles very slowly.
Fine particles of a substance that remain between the dissolution phase and the suspension phase. Colloids neither dissolve into other substances, remain suspended within the other substances nor settle out of the substances.
Particles suspended in a liquid, which are larger than molecular size but small enough to be moved about by molecular collisions. These particles do not settle under gravity. Their surface area is very large per gram, and the particles have a charge due to ions sorbed on the surface. This charge prevents coagulation or clumping of the particles and therefore, coagulation can be brought about by neutralizing the charge.
(Thomas Graham, 1861): state of a material consisting of extremely fine dispersed particles, (typically in a fluid), possessing diameters in one dimension in the range of 1 up to 1000 nm; see also nanoparticles
A colloid is something which "doesn't quite dissolve". In other words, it is neither like salt which quickly and totally dissolves in water, nor like sand which just as quickly and just as totally does NOT dissolve. It is tiny.
A substance of fine particle size, typically in the range of 0.1 to 0.001 microns, suspended in liquid or air. Such fine particles cannot normally be filtered out but are removed by reverse osmosis, distillation, or ultrafiltration process.
A colloid is a heterogeneous mixture composed of tiny particles suspended in another material. The particles are larger than molecules but less than 1 µm in diameter. Particles this small do not settle out and pass right through filter paper. Milk is an example of a colloid. The particles can be solid, tiny droplets of liquid, or tiny bubbles of gas; the suspending medium can be a solid, liquid, or gas (although gas-gas colloids aren't possible).
a substance made up of a system of particles with linear dimensions in the range of about 10 to 5 X 10 centimeters, dispersed in a continuous gaseous, liquid, or solid medium whose properties depend on the large specific surface area. Particles in a colloidal system remain dispersed indefinitely.
Very finely divided solid particles which will not settle out of a solution; intermediate between a true dissolved particle and a suspended solid which will settle out of solution. The removal of colloidal particles usually requires coagulation to form larger particles which may be removed by sedimentation and/or filtration.
A substance that, when suspended in water, diffuses not at all or very slowly through a semi permeable membrane, and usually has little influence on freezing point, boiling point, or osmotic pressure of the suspension; a substance in a state of fine subdivision with particles from 1 micron to 1 millimicron.
A finely divided organic substance which tends to inhibit the formation of dense scale and results in the deposition of sludge, or causes it to remain in suspension, so that it may be blown from the boiler.
A stable system of small particles dispersed in something else. A multi-phase system in which one dimension of a dispersed phase is of colloidal size. Colloids are the liquid and solid forms of aerosols, foams, emulsions, and suspensions within the colloidal size class. Milk and smoke are both colloids. Colloidal size is typically.001 micron to 1 micron in any dimension. Dispersions where the particle size is in this range are referred to as colloidal aerosols, colloidal emulsions, colloidal foams, or colloidal suspensions.
Gooey substances, usually proteins and starches, whose molecules can hold large amounts of a solvent (usually water) without dissolving. In lifeforms, virtually all fluids are held suspended in protein or starch colloids (hydrogels). Examples: cell protoplasm.
A type of solution. Glue like substance (like a protein or starch) whose particles remain uniformly distributed when dispersed in a solvent to the greatest possible degree. Colloids fail to form true solutions.
A mixture (very like a solution or a suspension) where very fine particles are dispersed in a second substance in such a way that they cannot easily be filtered out or settled. The particles are so tiny that they measure between 10 to 10,000 angstroms in size. find all NHC pages containing: colloid
In general, a colloid or colloidal dispersion is a substance with components of one or two phases, a type of mixture intermediate between a homogeneous mixture (also called a solution) and a heterogeneous mixture with properties also intermediate between the two. Typical membranes restrict the passage of dispersed colloidial particles more than they restrict the passage of dissolved ions or molecules; i.e. ions or molecules may diffuse through a membrane through which dispersed colloidal particles will not. The dispersed phase particles are largely affected by the surface chemistry existent in the colloid.
State of subdivision of matter which comprises either single large molecules or aggregations of smaller molecules in a dissimilar vehicle, usually held separate (prevented from peptization) by molecular potential or chemical additives.