the crystals

Crystallization - This technique is used for obtaining a compound in pure solid form of well-defined geometrically shaped crystals. This process of crystallization can be used for the purification of a compound only when the compound and the impurities present in it di..

Crystals are solid particles bounded by plane surfaces, which make definite angles with each other. This gives a definite geometrical shape to the crystal. These shapes are different for different crystals (Fig.6.13). Crystals of the same substance are ..

This method is used to separate a solid compound in pure and geometrical form. A nearly saturated solution of an impure substance is prepared in a hot solvent. The prepared solution is quickly filtered and the filtrate is then allowed to cool slowly in a china dish. The resulting pure crystal..

Large, well formed crystals can be obtained, by the slow evaporation of a cold and saturated solution of the substance. A large crystal can be grown by suspending a small well formed crystal, in a cold and saturated solution of the substance. The solution must be taken..

When the crystals are unstable, they are gently pressed between the folds of filter papers, and are finally placed in a vacuum desiccator to obtain dry crystals. If the substance is stable and has a high melting point, the crystals are pressed between the fold of the ..

If the impure compound is a mixture of two compounds whose solubility in any solvent does not differ significantly from one another, then the two compounds are separated by fractional crystallization. This is a series of repeated crystallisations. For instance when a solution containing ..

According to third law of thermodynamic it is only at OK that true crystals passes perfect order of arrangement of atoms in pure crystals. But with rise in temperature some derivations from complete order takes place. Presence of impurities also adds to disorde..

Water of Crystallization - When crystals of certain salts are formed, they do so with a definite number of molecules of water, chemically combined in a definite proportion. Water of crystallization is the number of water molecules, chemically combined in a definite mol..

In covalent crystals, the constituent particles are atoms of the same or different kind, which are bonded to one another by a network of covalent bonds. The important characteristics of covalent crystals are: The covalent crystals are incompressible and hard. The..

When certain salts form crystals with a definite number of molecules of water, they chemically combine to do so in a definite proportion. Thus, the water of crystallisation is the number of water molecules that combine chemically in definite molecular proportion, with the concerned ..