A mixture is a blend of two or more substances when each of them has its own identification and properties. The resultant mixture can be solid, liquid, or gas. Primarily, a mixture can be homogeneous or heterogeneous. A homogeneous mixture has a uniform composition of atoms or molecules whereas a heterogeneous mixture has a non-uniform composition throughout the mixture.
The above illustration shows that a homogeneous mixture has a uniform distribution of atoms of the substance all across the mixture. On the other hand, a heterogeneous mixture has different layers of atoms that are usually physically separable.
Difference between homogeneous and heterogeneous mixtures
|Homogeneous Mixture||Heterogeneous Mixture|
|Homogeneous mixture has throughout uniform solution composition||Heterogeneous mixture has non-uniform solution composition|
|Separation in individual liquids cannot be seen by naked eye||Separation in individual liquids can be seen through the naked eye|
|Atoms or molecules are evenly distributed throughout the solution||Atoms or molecules are non-uniform in the solution|
|Homogeneous mixtures have single phases||Heterogeneous solutions contain two or more phases|
|This mixture is not physically separable||It is an easily separable mixture|
|Smaller particles constitute the mixture||Larger particles constitute the mixture|
|Individual components have same physical properties||Individual components have different physical properties|
|They are more stable||They are less stable|
|They have more solvation capacity||They have less solvation capacity|
|Solution is an example of a homogeneous mixture||Suspension is an example of a heterogeneous mixture|
What is a Homogeneous Mixture?
The word ‘Homo’ comes from the Greek ‘homos’ meaning ‘same’. A homogeneous mixture is composed of particles that are evenly distributed throughout the mass. The best example of a homogeneous mixture is a solution of sugar and water. When sugar is dissolved in water, the sugar molecules are uniformly distributed between the water molecules. Both are in a liquid phase and cannot be separated physically.
Homogeneous mixtures can be separated by the processes of evaporation, chromatography, and distillation.
Examples of Homogeneous mixtures
- Air is the best example of a homogeneous mixture.
- Natural gas is a mixture of many gases used as fuel.
- Alloys are a mixture of two or more metals that contain a single phase like brass, steel, bronze, silver, etc.
- The chemical solution of similar phases is a homogeneous mixture. e.g. the solution of sugar in water.
- Chemicals used in daily life like dishwashing liquids, vinegar, etc.
- Saltwater is a homogeneous mixture until the concentration of salt increases the dissolution limit.
- Coffee and tea are good examples of homogeneous mixtures.
- Breathing analogs of air such as heliox, nitrox, etc.
- Seawater makes a good example of homogeneous mixtures when only dissolved gases are concerned.
- Perfumes are homogeneous mixtures as well.
- All perfect solutions are considered homogeneous mixtures.
What is a Heterogeneous Mixture?
The word ‘hetero’ comes from the Greek ‘heterogenès’ or meaning ‘different’. Heterogeneous mixtures are mixtures having a non-uniform composition of atoms or molecules throughout the mixture. These mixtures are always having separate phases that do not mingle with one another. The space between the two such phases is called interphase.
An interface is an important chemical term meaning the presence of both types of individual phases in a certain region of space where all the properties are essentially different from their surroundings. It is an essential parameter of the heterogeneity of heterogeneous mixtures.
The components of heterogeneous mixtures are much different in chemical nature so a physical separation is usually seen due to the force of gravity. The heavier component is pulled downward, and the lighter one remains up. An example of such a heterogeneous mixture is water and oil, etc.
The individual components of heterogeneous mixtures can be separated via handpicking, filtration, sedimentation, distillation, magnetic separation, threshing, winnowing, and separatory funnels, etc.
Examples of Heterogeneous mixtures
- Earth’s atmosphere is a heterogeneous mixture because the components of the atmosphere are not equally distributed.
- The mixing of two solid substances results in a heterogeneous mixture like sand and water, vegetables such as salad, etc.
- The combining of two different phases such as salt and oil, insoluble crystals in water, are examples of heterogeneous mixtures unless there is proper dissolution by any means.
- All immiscible liquids make heterogeneous mixtures such as oil and water, etc.
- Blood is an example of a heterogeneous mixture containing both solid and liquid components.
- The mixture of bitumen and asphalt is heterogeneous in nature.
- Soil and sand are mixtures of different types of materials so they are heterogeneous too.
- Medicine syrups and solutions are usually mixtures with multiple phase components. This is the reason, why the ‘shake well before use’ policy is advised.
- All suspensions and colloids are considered heterogeneous mixtures.
Heterogeneous vs homogeneous on the basis of the state of matter
|State of Matter||Type of Mixtures||Examples|
|Gas in Gas||Homogeneous||Air, atmosphere, etc|
|Liquid in Gas||Heterogeneous||Fog, mist, etc|
|Solid in Gas||Heterogeneous||Dust particles in air, etc|
|Gas in Liquid||Heterogeneous||Carbonated beverages, etc|
|Liquid in Liquid||Homogeneous||Alcohol in water, etc|
|Solid in Liquid||Heterogeneous||Mud in water, Medicinal syrups etc|
|Gas in Solid||Heterogeneous||Gases adsorbed on metal surfaces, etc|
|Liquid in Solid||Heterogeneous||Amalgams, etc|
|Solid in Solid||Homogeneous||Alloys, etc|
Key Difference between Homogeneous and Heterogeneous mixtures
What are the two types of mixtures?
There are two types of mixture
- Homogeneous mixtures
- Heterogeneous mixtures
Is soft drink a homogeneous or heterogeneous mixture?
The soft drink contains carbon dioxide, water, and sugar, etc. We cannot separate these components physically. Moreover, they are in different phases. That’s why soft drinks are heterogeneous mixtures.
Is air homogeneous or heterogeneous?
Air is a homogeneous mixture because it is composed of a mixture of gases that are in a single phase. Secondly, it is evenly distributed which means it has a uniform composition.
In which engines are homogeneous and heterogeneous mixtures used?
Internal combustion engines are of two types. Combustion Ignition (CI) engines use heterogeneous mixtures as fuels while Spark Ignition (SI) engines use homogeneous fuel mixtures.
Diesel engines use heterogeneous mixtures.
Is a solution a heterogeneous mixture or a homogeneous mixture?
Solutions are homogeneous mixtures because they contain a uniform composition of atoms or molecules throughout the sample.
Is ink a homogeneous or a heterogeneous mixture?
Ink is a homogeneous mixture because its molecules are evenly distributed throughout the mixture and they are in a single phase.
Is O2 in air a homogeneous or a heterogeneous mixture?
Oxygen in the air and many other substances make up air which is a homogeneous mixture.
Is simple water a heterogeneous or a homogeneous mixture?
Yes, water is a homogeneous mixture because it contains different minerals and ions which are in the same phase and a uniform overall composition is observed.
Is mud homogeneous or heterogeneous?
Mud is heterogeneous. It contains smaller particles of stones, sand, and soil. Their compositions are not uniform and they can be easily observed through a naked eye.
What is a homogeneous and heterogeneous system?
We can refer to a system to be homogeneous if it is composed of a uniform composition of particles otherwise it will be a heterogeneous mixture.
What are the properties of a homogeneous mixture?
Homogeneous mixture components must contain a single phase. Their chemical properties should be identical and they must contain uniform composition throughout the mixture.
Is pure sugar homogeneous or heterogeneous?
Pure sugar is not a mixture but if it is mixed with water it becomes a homogeneous mixture due to the solvation process.
Can the composition of homogeneous mixtures vary?
No. Homogeneous mixtures are the mixtures that have a uniform composition of particles.
Are water and vinegar a homogeneous or a heterogeneous mixture?
A mixture of water and vinegar is homogeneous because water molecules and vinegar molecules are in the same phase and evenly distributed. They are miscible too.
What is the difference between emulsions and heterogeneous solutions?
Emulsions are homogeneous mixtures that have the same phases and uniform compositions whereas heterogeneous solutions are composed of a non-uniform composition of molecules.
What kind of mixture is blood is water? Is it homogeneous or heterogeneous?
Water is a homogeneous mixture while blood is a heterogeneous mixture because blood can be separated by plasma. Their mixture is also a heterogeneous mixture.
Why is turbid water called a heterogeneous mixture?
Turbid water is unclear water and contains smaller particles of solid which can be seen through the naked eye. That’s why it is called a heterogeneous mixture.
Is air composed of nitrogen and oxygen, homogeneous or heterogeneous?
Air is a homogeneous mixture because it contains gas-phase molecules that are throughout uniform or evenly distributed.