Mixtures are pieces of matter formed by more than one substance. there are two types of mixtures: homogeneous and heterogeneous.
A heterogeneous mixture is distinguished from a homogeneous mixture by the variation of properties in its extension. While the homogeneous mixture has only one phase, the heterogeneous mixture is formed by at least two phases.
For example, water and oil is a heterogeneous mixture, as we can visually distinguish two phases with different characteristics in the mixture. A homogeneous mixture, such as water and salt, has the same properties in any part observed.
Homogeneous Mixtures
They are those in which you cannot tell the difference between two or more substances that make up the mixture.
They appear uniformly, in only one phase (monophasic). This is because the substances dissolve and actually become a solution.
Examples of homogeneous mixtures
- water and sugar
- Steel: mixture of iron and carbon
- Brass: mixture between copper and zinc
- Bronze: mixture of copper and tin
- Vinegar: mixture of acetic acid and water
- Saline: mixture of 0.9 g of sodium chloride and 100 mL of water
- Ethyl alcohol 96 ºGL: mixture formed by 96% ethyl alcohol and 4% water
- Atmospheric air: mixture of gases such as nitrogen and oxygen, among others (disregarding solid particles)
Learn more about chemical solutions.
Heterogeneous Mixtures
In heterogeneous mixtures, the presence of two or more substances in a mixture is clear. It has two or more phases (polyphasic). There are no gaseous heterogeneous mixtures.
Examples of heterogeneous mixtures
- Granite
- water and oil
- gold and sand
- sugar and flour
- Sulfur and iron filings
- Granite: mixture of feldspar, magnetite, mica and quartz
- Carbonated water (we can distinguish the bubbles of carbon dioxide in the water)
Also read about pure substances and mixtures.
Colloidal Mixtures
Although they appear to be homogeneous to the naked eye, as the difference between the mixtures is not noticeable, these mixtures are heterogeneous. This is because this difference becomes clear through the use of instruments.
Examples of colloids
- Blood: apparently homogeneous, through the microscope it is possible to verify that it is composed of blood cells, platelets and plasma.
- Milk: also with a uniform appearance, milk is composed of water, fat, proteins, among others, which can only be seen through laboratory analysis.
know about colloids and solute and solvent.
Mixture Separation Methods
There are several ways to separate heterogeneous mixtures, including scavenging. Picking is a type of manual mixing separation, the most common example of which is the removal of impurities from food, as we do daily before preparing rice.
Methods of separation of heterogeneous mixtures:
- Centrifugation
- Decantation
- filtration
- magnetic separation
- Levitation
- sieving
- Ventilation
Homogeneous mixtures, in turn, have to undergo chemical processes. The main ones are: simple distillation and fractional distillation.
The same happens with colloidal mixtures. These, necessarily, have to be separated by chemical processes.
You may also be interested in:
- Separation of Mixtures
- Simple and compound substances
- Exercises on homogeneous and heterogeneous mixtures
