Write the principle of the following :
(a) Zone refining
(b) Froth floatation process
(c) Chromatography
(a) Zone refining is based on the principle that the impurities on more soluble in molten state than in solid state of metal.
(b) Froth floatation process is based on the principle that the metallic sulphide particles of ore are preferentially wetted by oil and the gangue particles by water. Collectors attach themselves by polar groups to grains of minerals which then become water repellent and thus, pass on into the froth.
(c) Chromatography is based on the principle where molecules in mixture applied onto the surface or into the solid, and fluid stationary phase (stable phase) is separating from each other while moving with the aid of a mobile phase