True solutions are homogeneous mixtures of two or more compounds, whereas colloidal solutions and suspensions are heterogeneous combinations of two or more substances. Another difference between these three types of solutions is that the true solution is transparent, whereas the colloidal is translucent and the suspension is opaque.

In chemistry, solutions are defined as a mixture of two or more substances in which a solvent is present in liquid form and a solute is present in any of the three states of matter (liquid, solid, or gas). There are many various types of solutions, each with its own set of characteristics, however, they may be broadly classified as true solutions, colloidal solutions, or suspension solutions.

True Solution

The true solution is a homogeneous combination of two or more substances in which the solute is dissolved in the solvent. 

• The particles are less than 1 nm in size in this case. 
• When sugar or salt is dissolved in water, this is an example of a real solution. 
• Filter paper or parchment paper will not be able to filter or separate the particles. 
• The particles themselves are undetectable to the human eye.

Because the solution is in the liquid phase and clear, light may flow through it without being dispersed. When a solution is described as homogeneous, it indicates that the particles are spread uniformly throughout the solution and do not sink to the bottom of the container. The particle density is larger because the number of particles per unit volume of the solution is the same everywhere.

In a true solution:

• The light must not disperse. 
• Filtration would be unable to discriminate between the constituents of a true solution. 
• The Brownian effect, as well as the Tyndall effect, are not detected.

Colloidal Solution

A colloidal solution is a heterogeneous combination of two or more substances with particle sizes ranging from 1 to 1000 nanometers. 

• A colloidal solution is a mixture of true solution and suspension, albeit it is still in the liquid phase. 
• Colloidal solutions are made up of microscopic particles that float instead of being dissolved
• For example, starch dissolved in water or gelatin combined in water.

Similar to the actual solution, the colloidal solution particles are invisible to the naked eye but may be seen using an electron microscope.

The separation of colloidal particles may be accomplished using parchment paper, but not using filter paper. The particles can be obtained using a centrifugation procedure, in which they (particles) settle to the bottom. The particles in the solutions are not equally distributed due to the heterogeneous nature of the combination.

• Colloidal solutions are transparent
• They enable light to flow through the liquid, but the light is dispersed due to the presence of particles. 
• The colloidal solution exhibits Brownian motion and the Tyndall effect. 
• Reversible or irreversible emulsion, foam, sol, hydrocolloid colloids come in a variety of shapes and sizes.

Physical Properties of Colloidal Solutions:

• Heterogenous: Although colloidal solutions are heterogeneous, the dispersed particles present in them are not visible to the naked eye, giving the impression that they are homogeneous. This is the case because colloidal particles are too minute to be seen with the human eye.
• Filterability: Colloidal particles pass through regular filter paper due to their small size. Animal membranes, cellophane membranes, and ultrafilters, on the other hand, can retain them.
• Stability: Lyophilic sols in general and lyophobic sols in the form of significant electrolyte concentrations are quite stable. The dispersed particles included do not settle down even after prolonged storage. However, a few bigger colloidal particles may progressively sediment after a lengthy period.

The size of the colloidal particles in a colloidal solution determines the colour of the solution. Larger particles absorb longer-wavelength light and transmit shorter-wavelength light as a result. For example, silver particles of 150nm appear violet, while those of 60nm seem orange-yellow.

Suspension

Suspensions are mixtures in which the particle size is greater than 1000 nm. When dirt is dissolved in water that is vigorously churned, the particles of the solution settle at the bottom of the container after a while due to gravity; this is an example of a suspension.

The particles in the real solution can be seen with the naked eye. Suspension exhibits Brownian motion and the Tyndall effect.

Conclusion

The solution is defined in chemistry as a combination of two miscible or immiscible compounds in a liquid or gas media. In this article, we discussed the three sorts of solutions, their qualities, and Colloidal State Distinction Between True Solutions. Colloids are medium with dissolved or scattered particles ranging in size from 1mm to several microns. A colloidal system has a dispersed phase and a dispersed medium. A true solution is a homogeneous mixture that comprises particles mixed in the correct composition and adequately dissolved.