Homogeneous vs heterogeneous
In most technical applications homogeneous means that the properties of a system are the uniform throughout the entire system; heterogeneous (also inhomogeneous) means that the properties change within the system.[1] Any system with two phases like ice and water are said to be heterogeneous.
For example, homogeneous systems have the same composition, density and pressure throughout. A homogeneous system will often have more than one component (like salt and water), but the mixture will be uniform throughout the sample.
For a heterogeneous system there may be clumping of salt in the salt water, or parts of the water that are saltier than others. Figures 1 and 2 below show how heterogeneous and homogeneous systems differ.
- Heterogeneous and Homogeneous Gas Particles
![Figure 1. A heterogeneous mixture of molecules in a gas. Note that: the density (and pressure) is different throughout.[2]](/encyclopedia/File:Heterogeneous.PNG)
![Figure 2. A homogeneous mixture of molecules in a gas. Here, the density (and pressure) is uniform throughout.[2]](/encyclopedia/File:Homogeneous.PNG)
These terms are also important for catalysis. For information on homogeneous vs. heterogeneous catalysis please visit the Chem Guide.
For Further Reading
- Pressure
- Density
- Phase change
- Or explore a random page
References
- ↑ A Dictionary of Chemistry (7 ed) by Richard Rennie, published 2016.
- ↑ 2.0 2.1 Image made by a member of the energy education team by using the PhET resource found here: https://phet.colorado.edu/en/simulation/gas-properties, Accessed July 14th, 2017.