A mixture is a physical mixing of two or more different chemical species to form a new whole. The chemical identities of the individual components, however, are not changed and no chemical reaction has taken place. The different chemical species could be separated from each other to their prior unmixed state, even though that might be very tedious.
There are two major types of chemical mixtures, heterogeneous and homogeneous. A homogeneous mixture is one where the mixture has a single phase, or visible medium (homo meaning same). Any random sample from the mixture would look exactly the same as any other random sample from the mixture. An example is a mixture of salt or sugar in water. The solid dissolves completely, thus giving the mixture a consistent, uniform look.
A heterogeneous mixture is one where the mixture has two or more visible phases (hetero meaning different). An example of this would be sand in water. The sand is not soluble, so you will see the individual grains sitting in the water.
Mixture is a combination of two substances that retain their physical identities after combining and can be separated by physical methods such as distillation, evaporation, crystallization, or filtration.
There are two types of mixtures:-
- Homogenous Mixtures
- Heterogeneous Mixtures
Homogenous mixtures are those mixtures in which when two or more substances are combined, forming a solution in which the substances used cannot be depicted.
- Have uniform composition
- All solutions are homogenous mixtures
- It has no visible boundaries of separation between its constituents
- Sugar Solution
- Salt Solution
Mixtures made of two or more substances that when mixed together forms a mixture in which the substances used can be depicted.
- Have non-uniform composition
- All suspensions are heterogeneous mixtures
- It has visible boundaries of separation between its constituents
- Mixed nuts
- Cereal in milk
Homogenous mixtures are completely mixed. The solute has dissolved in the solvent, creating one single mixture. When you look at the mixture, you should not be able to depict various substances, but one single substance. An example of a homogenous mixture is salt in water. Once dissolved, you cannot see the individual grains of salt.
Heterogenous mixtures are the exact opposite. You can clearly see two different substances in the vial/test tube/etc. An example of a heterogeneous mixture is aluminum foil in water. No matter how small you make the foil pieces, you can clearly see the foil in contrast to the water.