van der Waals’ force

Trends in Physical Properties of Group 17 Elements

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During the period 1811-1886, the halogens were discovered. They are non-metallic elements such as: Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I) and astatine (At) which are the members of the halogen family. This family constitutes the group 17 of the periodic table. The word halogens have been derived from the Greek word “Halo” that … Read more

Multi-molecular, Macromolecular and Association Colloids

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Colloidal solutions can also be classified on the basis of constitution of the particles of the dispersed phase. The tree types of colloids are given as below: A) Multi-molecular Colloids This is the type of colloid in which the colloidal particles consists of aggregates of atoms or small molecules, having diameters of less than 1nm. … Read more