electrical properties of colloids

Colloidal particles of a sol either carry positive or negative charge. Sols in, which the colloidal particles carry positive charge are called positive sols. When colloidal particles carry negative charge, the sols are called negative sols. The existence of charge on t..

Heterogenous nature - Colloidal sols are biphasic in nature. It consists of the dispersed phase and the dispersion medium. In the colloidal solution, each particle is contained within its own surface boundary and therefore has a separate existence from the dispersion mediu..

Brownian movement - When a colloidal solution is viewed through a powerful microscope, the colloidal particles can be seen moving in a random zig-zag path. This zig-zag motion of colloidal particles is called Brownian movement. This random motion is due to collisions b..

Properties of solids have been exploited for various new innovations in electronic and magnetic devices like transistors, computers, telephones etc. Properties of the solids mainly depend upon their structure and composition. Three main properties are discussed belo..

Additivity - If a system consists of two point charges q 1 and q 2 , then the total charge of the system is got by adding q 1 and q 2 . Thus, the charge add up like real numbers (scalars). When we add charges, one should take care of its sig..

Interaction between Colloids-Gold Number - It is known that lyophobic sols are unstable. They are however stabilized by adding stabilizers. When two lyophobic sols are mixed together, they may coagulate by mutual neutralization of electric charges or by destroying each others st..

Property True solutions Colloidal solutions Suspensions Particle size Less than 10 - 7 cm Between 10 - 5 and 10 - 7 cm Greater than 10 - 5 cm Visibility of particles Invisible to naked eye not visible under powerful microscope Inv..

Static electricity was known to people more than 2500 years ago. The Greeks knew about the attractive property of the resin amber. They knew that by rubbing amber with cloth, it could be made to attract small feathers. The Greek name for amber was 'elektron..