Solutions are homogeneous mixtures through which light can pass, whereas suspensions are heterogeneous mixtures that cannot allow the light to pass through. The main difference between solution and suspension is that the solute particles can not be seen (by the naked eye) in solutions whereas, in suspensions, those particles can easily be seen.
Solutions contain solute particles with a size of less than 1 nm while suspensions have solute particles that measure more than 1000 nm. This makes the fact, solutions are transparent while suspensions are cloudy, true. Moreover, solutions are homogeneous mixtures while suspensions are necessarily heterogeneous mixtures.
Solutions vs suspensions
| Solutions | Suspension |
| Solutions are homogeneous mixtures | Suspensions are heterogeneous mixtures |
| The size of particles in solutions are very small | Suspensions have large sized particles |
| Solutions are transparent when exposed to light | Light cannot pass through the suspensions |
| Solute takes the properties of solvent in solutions | Solute has its own distinct properties in suspensions |
| The components of solutions cannot be separated by filtration | The solute can be separated from solvent by filtration |
| NaCl in water, sugar in water, sublimes in air are examples of solutions | Oil in water, dust in air are examples of suspensions |
Related topics
- Homogenous vs. Hetrogenous solutions
- Solubility factors
- Solvent extraction technique
- Polar and nonpolar solvents
What are Solutions?
A solution consists of two components:
- Solute
- Solvent
Solutions are homogeneous mixtures of two or more components, where the one with a minor amount is known as solute and the one with a major amount is known as a solvent.
Generally, there are three types of solutions:
1. Unsaturated solution
An unsaturated solution is a solution having more capacity to dissolve solute than it already has, at that particular temperature.
2. Saturated solution
A saturated solution is a solution having a maximum quantity of a solute dissolved at a particular temperature.
3. Supersaturated solution
A supersaturated solution contains more amount of solute than the maximum amount of solute for a particular temperature. It is prepared at high temperatures as a virtue of the direct relationship between temperature and solubility.
Examples of solutions with their applications
| Solute | Solvent | Final solutions | Examples |
| Solid | Solid | Solid | Alloys |
| Solid | Liquid | Liquid | Sugar, salt dissolved in water |
| Solid | Gas | Gas | Dust particles in air |
| Liquid | Solid | Solid | Amalgam of mercury in sodium |
| Liquid | Liquid | Liquid | Ethanol in water |
| Liquid | Gas | Gas | Moisture(water vapors) in air |
| Gas | Solid | Solid | Hydrogen gas adsorbed on Palladium |
| Gas | Liquid | Liquid | Carbonated drinks |
| Gas | Gas | Gas |
Air (mixture of N2, O2, Noble gases, etc) |
What are Suspensions?
A heterogeneous mixture in which particles of solid are suspended throughout the liquid is known as a suspension. Solute particles do not dissolve properly in solvents and result in cloudy emulsions that do not let the light, pass through properly.
Suspensions usually result in mixtures that settle down due to the effect of gravity. Ideal suspensions in such a case will be the ones that redistribute upon shaking. Suspension particles have the capability to form sediments or cakes, upon compression which are then difficult to redisperse.
Suspension based hydrocarbon ointments, suspension type aqueous gels, milk of magnesia, oil in water and dust in the air are some examples of suspensions.
How to identify solutions, suspensions, and colloids
To differentiate between solutions, suspensions and colloids, the light passes through these mixtures.
- A solution is always transparent through which light can pass and there is no overall scattering of light.
- A colloid is an intermediate between solutions and suspensions. It gives the Tyndall effect by scattering the passing light.
- A suspension is cloudy and suspended particles can be seen through naked eyes. Light cannot pass through the suspensions.
Solution vs Colloids vs Suspension
| Solutions | Colloids | Suspensions |
| Solutions are homogeneous mixtures | Colloids are heterogeneous mixtures | Suspensions are heterogeneous mixtures |
| They have very small particles | They have intermediate particles (1-1000 nm) | They have large size particles (more than 1000 nm) |
| Solutions are transparent when exposed to light | Colloids gives Tyndall effect (Scattering of light) | Light cannot pass through suspensions |
| Solute takes the properties of solvent in solutions | Colloids are in fact a type of suspensions | Suspensions have intermediate properties of solute and solvent |
| The components of solutions cannot be separated by filtration | Colloids particles can be separated by ultra-filtration | Suspensions can be separated by ordinary filtration |
| salt, sugar dissolve in water, sublimes in air are examples of solutions | Foams (shaving cream), gels (gelatin), emulsions (lotions), are examples of colloids | oil in water, dust in air are examples of suspensions |
Key Takeaway(s)
- Solution is defined as a homogeneous mixture of solvent and solute with particle size less than 1 nm.
- Suspension is defined as a heterogeneous mixture of solvent and solute with a particle size of more than 1000nm.
Concepts berg
What are examples of suspensions?
Some common examples of suspensions are as follow:
- Oil and water
- Muddy water
- Dust in air
- Paints
- Sand in water
- Milk of magnesia, etc
Solution and Suspension similarities:
- Both solution and suspension have two or more components.
- Both solution and suspension are mixtures (the components are not bonded chemically).
- Solution and suspension particles are separated on the basis of their physical properties.
What is a mixture?
A mixture is formed by the combination of two or more substances that are not chemically combined.
Types: Homogeneous and Heterogeneous mixtures
Example: Solutions, Suspension, Colloids.
What is dispersion in chemistry?
Dispersion in chemistry is the distribution of particles of one substance, scattered in a continuous phase of another substance.
Explain colloids?
The colloids are heterogeneous mixtures in which their particle size is intermediate between solutions and suspensions. The particles of colloids are dispersed throughout the dispersion medium evenly. These particles are not separated by ordinary filtration techniques.
Foams, gels and emulsions are some examples of colloids.
Is water a solution or solvent?
Water is a pure substance(compound) that consists of hydrogen and oxygen only. Water is capable of dissolving more substances than any other liquid, that’s why it is known as a universal solvent.
Is Vinegar a solution or solvent?
Vinegar is a solution of acetic acid(CH3COOH) in water. It is usually 5% acetic acid in water.
Are there any solutions with no solvents?
Solutions always consist of two parts:
- Solute
- Solvent
References
- Pharmaceutical Emulsions and Suspensions (Second Edition), Revised and Expanded by Françoise Nielloud and Gilberte Marti-Mestres (Laboratoire de Technique Pharmaceutique Industrielle Universite Montpillier, Montpillier, France)
- How is a solution different from a suspension? (University of California, Santa Barbara)
