Application of Colloids

Colloids are mixtures of chemically microscopic components that are insoluble in nature and the particles of one substance are dispersed into another substance. The particles that are suspended in a colloidal mixture can vary between one to one thousand nanometers. For a mixture to be categorised as a colloid, the particles that are dispersed into each other should not settle. Another property that can be used for the identification of a colloidal solution is the tyndall effect. According to this property a beam of light scatters when it collides with the particles that are dispersed throughout the colloidal mixture. In a colloidal mixture the substance that is dispersed is referred to as the dispersed phase and the stance into which the other substance is dispersed is referred to as the continuous phase. 

Preparation of a colloidal mixture

For the preparation of colloidal mixtures, it is necessary to maintain some interaction between the dispersed phase and the continuous phase so that the colloid is stable. A method that is used for the preparation of colloids is called the condensation method. In the condensation method, the solute particles of a solution are condensed so that they can convert into the dispersed phase of a colloid. The process of condensation can occur by both chemical and physical methods. Another method that is used for the preparation of colloids is the dispersion method. In the dispersion method, the particles of a larger substance are physically or chemically broken down into smaller insoluble particles. 

Examples of colloidal mixture

There are several examples of colloidal mixtures that are used in day to day lives. Colloids are preferred over other kinds of solution because the particles that are a part of the colloids possess a certain level of thermal kinetic energy that helps in providing them with mobility. This solution shows negligible inertial and gravitational effects. There are several types of colloidal solutions that are formed due to the difference in the dispersed phase and the continuous phase. Some colloids have liquid as their dispersed phase and gas as their continuous phase. Some examples of such colloids include fog and smog. Some colloids have solid as their dispersed phase and gas as their continuous phase. Some examples of such colloids are smoke and dust in the air. Some colloids have liquid as both their dispersion and continuous phases. An example of such colloids include milk. 

Applications of colloids- 

Colloids are used in various fields in our day to day lives and hence, they have several applications. Medicines that occur in the form of colloidal mixtures tend to get absorbed by the body tissues much faster than the other forms. Hence, such medicines are preferred over others. Sewage acts as one of the major factors of water pollution. However, the particles present in sewage make up a colloid that possesses a negative electric charge. If the sewage is passed through electric plates that possess an opposite electric charge then the waste particles would settle down. This method can also be used for the purification of drinking water. In the case of drinking water, the impurities can be made to settle down by adding certain chemical compounds such as alum. These chemical particles stick to the impurities and help them in settling down. The soap particles are also colloidal in nature. 

The colloidal nature of the soap solution helps them in sticking to the dust and dirt particles and enhances their cleansing action. Colloids also have major geographical applications. One such application is the ability of colloidal sea water in the formation deltas. Sea water is considered to be a large source of colloidal particles and electric charge. When this comes in contact with sand it leads to the precipitation of sand particles which in turn elevates the base of the rives. Due to this the flow of the river is often changed. Smoke is a mixture of solid particles that are dispersed in air. They possess some electric charge and this charge interacts with electric plates that possess an opposite charge and the process is known as smoke precipitation. Colloids also help in the formation of artificial rain. This is achieved by spraying oppositely charged dust and sand particles over a cloud. This results in the neutralisation of the colloidal water particles that are present in the cloud and leads to precipitation. 

Conclusion :

Hence, it can be concluded that colloids are chemical mixtures that have two different or similar types of particles dispersed into one another. The colloidal solutions are stable and they are used in several fields in the day to day lives of humans. The colloids consist of a dispersed phase and a continuous phase. They have several applications in the field of medicine, in smoke precipitation, purification of water etc.