Homogeneous Mixtures: Introduction
When 2 or more substances are mixed in any proportion, then this combination is defined as a mixture. Mixtures can be separated by physical methods such as evaporation, distillation, etc.
For example; salt and water, where 2 different components are mixed to form a mixture.
Mixtures can further be classified into homogenous and heterogeneous mixtures.
A Homogenous mixture is defined as the mixture where the composition is the same that is components are mixed uniformly.
Example; sugar and water.
A heterogeneous mixture is defined as the mixture where components are mixed non-uniformly, thus form 2 separate layers.
For example; soil and water are 2 different components that do not mix and thus form a layer and can be seen through a naked eye.
Homogeneous is derived from two words ‘homo’ meaning the same and geneos meaning ‘group/type’. Thus homogeneous means having the same or uniform composition.
A solution is a homogeneous mixture for example lemonade is a solution of lemon and water. The components of the solution are solute and solvent. The solute is dissolved in a solvent that is present in a larger quantity.
For example; a solution of sugar in water where sugar is the solutes taken in small quantity and water is the solvent taken in larger amounts.
Characteristics of Homogeneous Mixtures
The homogenous mixture/solution has only one phase that is solid, liquid and gas. Examples for the same are;
Solid homogeneous mixture: brass is an alloy that is made from metal copper (Cu) and zinc (Zn).
Liquid homogeneous mixture: a saline solution that is the mixture of water and salt.
Gas homogenous mixture: air is a mixture of different gases such as oxygen, carbon dioxide, nitrogen, and many more gases present in smaller amounts in the environment.
The size of particles of the solution is smaller than one nanometer thus homogenous mixtures do not show the Tyndall effect and cannot be seen with the naked eye.
The solute particles do not settle down when left uninterrupted, thus, a solution is stable.
Homogeneous Mixtures Examples
1. Salt and water.
2. Alcohol and water.
3. Steel is an alloy made from copper and iron.
4. Bronze is an alloy which is a mixture of copper and tin.
5. Natural gas is a mixture of methane and other gases.
Types of Solutions
Dependent upon the dissolution of the solute in the solvents, solutions can be categorized into the following;
A supersaturated solution comprises a large amount of solute that can be dissolved by the solvent where the extra solute will crystallize quickly at a particular temperature. The most prevalent example is sodium acetate which is a supersaturated solution.
An unsaturated solution is a solution in which a solvent can dissolve any more solute at a given temperature.
A saturated solution can be defined as a solution in which a solvent is not capable of dissolving any further solute at a given temperature thus it means that the maximum amount of solute has been dissolved and further no more solutes can be dissolved in the given solvent.
Factors Affecting Solubility
The quantity of solute that can be dissolved in a solvent to form a saturated solution depends following factors given;
Temperature: Solubility is directly proportional to temperature thus it increases with temperature. For example, we can dissolve much more salt in hot water as compared to cold water.
Pressure: Increasing pressure can vigor more solute into solution. This is usually use to dissolve gases into liquids.
Chemical Composition: The nature of the solute and solvent and the existence of other chemicals in a solution affects its solubility. For example, we can dissolve much more sugar in water as compared to salt.
The solutions are of two forms, depending on the solvent if its water or not.
Aqueous solution: When a solute is dissolved in water then this type solution is called an aqueous solution.
For example; salt in water and sugar in water
Non-aqueous solution: When a solute is dissolved in a solvent other than water, then this type of solution is called a non-aqueous solution.
For Example; iodine in carbon tetrachloride, sulphur in carbon disulfide.
Homogeneous Mixtures Citations