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Classification of Colloid

Colloids are the type of mixtures which share the mean properties of both the mean properties of solutions and suspensions. The Classification of colloids is by different basis, the most important being the size and charge of colloidal particles.

Colloidal solutions are solutions in which colloidal particles are suspended. They are also known as colloidal suspensions. Colloids consist of a dispersed phase and a continuous phase. This is unlike solutions, in which the solvent and the solute form a single phase.

Colloidal solutions are solutions that contain colloidal particles. Colloids consist of a dispersed phase and a continuous phase, whereas solutions are composed of only one phase. The solute in a colloidal solution is in the form of individual molecules or ions, unlike the colloid, which is larger in size.

About Colloids 

Colloidal solutions are liquids that include tiny particles suspended in suspension. Colloids have a scattered phase and a continuous phase, whereas solutions have only one phase. In contrast to the colloid, which is greater in size, the solute in a colloidal solution is in the form of individual molecules or ions. Colloidal solutions endure better and are more stable than colloidal suspensions.

Colloids are particles that are smaller than the size of a liquid droplet. The size of colloidal particles range between 1 micrometre and 1 nanometre. They are dispersed in a continuous phase. The dispersed phase of a colloid may be a liquid, a solid, a gas, or a plasma. The continuous phase of a colloid is the surrounding medium.

The components of a colloid are separated by a continuous phase. This means that the molecules of the colloid do not all touch each other. The dispersed phase of a colloid is where the individual molecules or ions of the colloid are suspended in the continuous phase.

The classification of colloids is done at many levels, viz. Natural and synthetic colloids, Sols, Emulsions, foam and aerosols, and Multimolecular, Macromolecular and Associated colloids. 

About dispersed phase and dispersion medium 

The dispersion phase is the dispersed state of matter into which a colloidal solution has been stirred. The dispersed state is the result of the agglomeration, or clustering, of the colloidal particles. The dispersed phase is a colloidal solution in which the particles have dispersed into a liquid state. This transition, which occurs when the particles agglomerate, is called dispersion.

The dispersed phase in colloids is the tiny, solid material suspended inside a liquid. The dispersed phase is composed of numerous separate molecules that interact with one another and with the liquid medium to give the colloid its distinct features. The scattered phase is the most prevalent type of colloidal phase found in nature and many man-made items. The biological material in a cell, which contains proteins, DNA, and other molecules, is referred to as the dispersed phase of proteins in the body.

Dispersion media can be used in colloidal systems to prevent settling and improve colloid performance. The most common dispersion media are liquids such as water. Dispersion media are often used in colloidal systems as alternatives to traditional colloid stabilisers such as colloidal silica. Unlike colloidal silica, dispersion media can be used to prevent settling in suspensions and improve colloid performance.

Classification of Colloids

The classification of colloids is based primarily on the size of the colloidal particles. Particles that are smaller than 1 micron (1,000 nanometers) are classified as colloids. The colloidal particles can be classified further based on the state of matter in which they are found. Particles that are suspended in a liquid are called colloidal sols or suspensions, while colloidal particles that are suspended in a gas are called colloidal gels or aerogels.

  • Classification of colloids is according to how they are formed.
  • Emulsions are colloids formed when oil and water are mixed together. Gels are colloids formed when an organic molecule is used to trap water in an aqueous solution. 
  • Foams are colloids formed by gas bubbles in a liquid.
  • Classification of colloids is also based on how they are formed. Some colloids are formed when small particles are suspended in a liquid, or when a solid is suspended in a liquid. These colloids are called solution colloids. Other colloids are formed when large molecules are suspended in a liquid, or when a liquid is suspended in a liquid.
  • Classification of colloids is also according to  how they are dispersed, how large or small they are, and how well they are dispersed.  Three types of colloids are suspension colloids, solution colloids, and emulsion colloids. 
  •  Suspension colloids are colloidal particles suspended in a liquid dispersion medium.  Examples of suspension colloids include milk, blood, and soaps.

Multi molecular colloids

When smaller molecules are combined in a solvent, they clump together to produce multimolecular colloids. These tiny molecules should have a diameter of less than 1 nm in order to form colloidal particles (around 100 nm). As a result, the molecules that comprise multimolecular colloids have a lesser  molecular weight. The tiny molecules (or atoms) in these multimolecular colloids are kept in contact by Van der Waal forces. These colloids are often lyophobic. This implies that all these colloids have little or no contact forces with the dispersant.

Macromolecular colloids

The Macromolecular colloids are the classification of dispersion colloids whose particles are big enough to be termed colloids are referred to as macromolecular colloids (possessing diameter around 100 nm). These molecules are elevated compounds in terms of molecular weight attributes. Because of their huge molecular weight and massive dimensions, they are also known as macromolecules. Whenever these chemicals are mixed with a solvent, the suspended particles spread throughout the solution. This is referred to as a macromolecular colloid solution. This group includes the majority of lyophilic colloids. Lyophilic colloids are solvent-loving particles that may form strong contacts with their dispersion medium.

Conclusion 

A colloid solution is a heterogeneous combination with particles that are between the attributes of a solution and those of a suspension. The Colloidal particles are equally distributed throughout the dispersion medium, which might be a solid, liquid, or gas. Because the scattered particles of a colloid are not as massive as those of the particles in the suspension, colloidal particles do not settle down when the solution is still. 

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What are the most common examples of colloids?

Ans. Colloids are ubiquitous in everyday life. Condensed milk, salad cream, milk, buttermilk, collagen, gelatin, pud...Read full

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Ans. Colloids are best defined as mixes that contain 1 or more chemicals that are scattered as fairly large solid ma...Read full

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Ans. Classifications of colloids are by using two primary criteria they are- the affinity of the dispersed phase for the dispersion and the conditi...Read full