A homogeneous mixture is a mixture that has a consistent composition throughout. The components of a homogeneous mixture are evenly distributed, and it can be difficult to distinguish one substance from another. An example would be a solution where the solute is completely dissolved in the solvent.
On the other hand, a heterogeneous mixture is one in which the components are not evenly distributed, and different substances can be easily identified. In a heterogeneous mixture, the individual components retain their own properties, and they are often visible to the naked eye or can be easily separated.
Examples:
Homogeneous Mixtures:
- Saltwater: When salt is dissolved in water, it creates a uniform solution where the salt is evenly distributed.
- Air: The gases in air (such as oxygen, nitrogen, and carbon dioxide) are mixed together in a consistent ratio, making it a homogeneous mixture.
- Vinegar: A solution of acetic acid in water is uniform in composition and appears the same throughout.
Heterogeneous Mixtures:
- Salad: A salad is made up of various ingredients (lettuce, tomatoes, cucumbers), and the individual components can be seen and separated.
- Sand and gravel: In a mixture of sand and gravel, the different particle sizes and types can be easily distinguished from one another.
- Oil and water: When mixed, oil and water do not combine into a single phase; they remain separate layers, making it easy to identify each component.
In summary, the key difference lies in the uniformity of composition: homogeneous mixtures are uniform, while heterogeneous mixtures are not.