special properties of colloids

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 c..

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..

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..

In colloidal systems the number of colloidal particles per litre of the sol is relatively much smaller than solute particles in a true solution. Colloidal particles are aggregates of simple molecules and colligative properties such elevation in boiling point,..

Although a colloidal solution appears to be homogenous because the dispersed particles are too small too be seen, it can be distinguished from a true solution by its ability to scatter light. The scattering of light by colloidal sized particles is called the Tyndall effect. Thi..

When colloidal solutions have been observed through ultra microscope, the colloidal particles are seen in constant and rapid zigzag motion called Brownian movement. Sir Robert Brown first observed the phenomenon in 1827. Suspensions and true solutions do not exhibit Brownian mov..

Comparison of Properties of Electrovalent and Covalent Compounds - Property Electrovalent or ionic compounds Covalent or molecular compounds Structure of charged ions They consist of oppositely charged molecules They consist of uncharged or neutral molecules Physical state and h..

The thyroid gland secretes three hormones Thyroxine or tetraiodothyroxine, triiodothyronine and calcitonin . Thyroxine and triiodothyronine are iodinated forms of the aminoacid tyrosine. They are stored in the colloid that fills the vesicles and are released to the blood when needed. ..

. Colloidal system are classified in three ways depending on: i) Physical states of the dispersed phase and dispersion medium nature of interaction between the dispersed phase and the dispersion medium. ii) Colloidal systems exhibit their characteristic optical, mechanical and e..