The main difference between the true solution and the colloidal solution is that the true solution is a homogeneous single-phase system and the colloidal solution is a heterogeneous two-phase system.

True solutions vs. colloidal solutions

A true solution is a homogeneous mixture, whereas a colloidal solution is a heterogeneous mixture. The true solution is a one-phase system, while the colloidal solution is a two-phase system. The true solution is one in which the solute dissolves in solvent, while the colloidal solution is a two-phase system in which one phase is dispersed into another phase. The true solution consists of solute and solvent; on the other hand, the colloidal solution consists of the dispersed phase and the dispersion medium. The true solution is transparent in appearance, while the colloidal solution is translucent in appearance. The true solution contains particles that are invisible to the naked eye, while the colloidal solution contains particles that are visible under the electron microscope.

Comparative chart

The real solution is the homogeneous mixture. The true solution is prepared by a combination of two or more components. The true solution has solute and solvent. Between the two components of the true solution, the solute is present in less quantity and the solvent is present in large quantities, but in some cases there is an exception. The Solute in True solution can be solid, liquid or gaseous and the same goes for the solvent. When the two components of the True solution are combined, the environment of both components changes for dissolution. Solute molecules separate from similar molecules and then solvent molecules surround them. The solvent molecules also separate sufficiently from other similar molecules to create a space to accommodate the solute molecules. Solute dissolves in solution only when intermolecular forces in solute-solute and solvent-solvent are overcome by intermolecular forces in solvent-solute. If the solute is polar, then the intermolecular forces are stronger and the solute would dissolve in a solvent if the solvent-solute intermolecular forces are stronger than the intermolecular forces in polar solute molecules. This means that the solvent must also be polar. True solutions are formed on the basis of the solubility principle, which is how it dissolves. The strength of the True solution is expressed on the basis of molarity, molality, normality or on the basis of the mass or volume of solute dissolved in a specific mass or volume of solvent. The strength of the True solution can be expressed as a percentage.

Sugar solution

What is colloidal solution?

A colloidal solution is a system in which one substance is dispersed in another in the form of particles. The dispersed substances form the dispersed phase and the substance in which the dispersed substances are dispersed forms the dispersion medium. Colloidal solutions are classified according to the physical state of the two substances, that is, dispersed and dispersed substances. One substance disperses into another only when there is considerable contact between two substances. Colloidal solutions are of two types, lyophobic and lyophilic colloidal solutions but instead of these two general terms they are used as hydrophobic and hydrophilic. Hydrophilic colloidal solutions are those in which there is affinity of the dispersed particles for the dispersion medium. Hydrophobic colloidal solutions are those in which there is little or no affinity of the dispersed particles for the dispersion medium. Hydrophilic colloidal solutions are thermodynamically stable due to the affinity of the dispersed particles for the dispersion medium. So hydrophilic colloidal solutions form spontaneously as dispersed particles add to water. Hydrophilic colloidal solutions show spontaneous coalescence when dispersed particles are added to water. The interaction in the particles of the colloidal solution is due to some forces, such as those of the van der walls, the entropic forces, the steric forces, the excluded volume forces and the electrostatic interactions. The colloidal solution can be prepared in two ways. Colloidal dimensions are achieved by spraying, milling, and applying shear such as stirring or high shear mixing. Dissolved small molecules can be condensed into larger colloidal particles through a process such as redox reactions, precipitation, and condensation.

Starch dissolved in water

Key differences

1. The true solution constitutes a single-phase system, while the colloidal solution constitutes a two-phase system.
2. The true characteristics of the solution are a homogeneous mixture; On the other hand, the characteristics of the colloidal solution is a heterogeneous mixture.
3. The true solution has solute and solvent while the colloidal solution has dispersed and the dispersion medium.
4. The true solution has a solute particle size of less than 1 nm in diameter, while the colloidal solution has a dispersed phase particle size in the range of 1-1000 nm.
5. The true solution appears clear while the colloidal solution appears translucent.
6. The true solution has the property of electrolysis, while the colloidal solution does not have such property.
7. True solution particles are invisible to the naked eye, while colloidal solution particles are visible to the electron microscope.

Final Thought

The conclusion from the above discussion is that the true solution and the colloidal solution are homogeneous and heterogeneous mixtures respectively and find their use in chemistry and pharmaceuticals.