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Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. [1] The verb form of sublimation is sublime, or less preferably, sublimate. [2] Sublimate also refers to the product obtained by sublimation. [2][3] The point at which sublimation occurs rapidly (for further details ...
A sublimatory[1][2] or sublimation apparatus is equipment, commonly laboratory glassware, for purification of compounds by selective sublimation. In principle, the operation resembles purification by distillation, except that the products do not pass through a liquid phase.
Sublimation is the process of changing of any substance (usually on heating) from a solid to a gas (or from gas to a solid) without passing through liquid phase. In terms of purification - material is heated, often under vacuum, and the vapors of the material are then condensed back to a solid on a cooler surface.
The sublimated material collects (5) on the cold finger proper, cooled by a coolant (blue) circulated through ports 1 and 2. A cold finger is a piece of laboratory equipment that is used to generate a localized cold surface. It is named for its resemblance to a finger and is a type of cold trap. The device usually consists of a chamber that a ...
Distillation. Laboratory model of a still. 1: The heat source to boil the mixture. 2: round-bottom flask containing the mixture to be boiled. 3: the head of the still. 4: mixture boiling-point thermometer. 5: the condenser of the still. 6: the cooling-water inlet of the condenser. 7: the cooling-water outlet of the condenser.
Sublimation sandwich method. The sublimation sandwich method (also called the sublimation sandwich process and the sublimation sandwich technique) is a kind of physical vapor deposition used for creating man-made crystals. Silicon carbide is the most common crystal grown this way, though other crystals may also be created with it (notably ...
Crystallization. In chemistry, fractional crystallization is a stage-wise separation technique that relies on the liquid-solid phase change. It fractionates via differences in crystallization temperature and enables the purification of multi-component mixtures, as long as none of the constituents can act as solvents to the others.
The low temperature and direct sublimation to a gas makes dry ice an effective coolant, since it is colder than water ice and leaves no residue as it changes state. [4] Its enthalpy of sublimation is 571 kJ/kg (25.2 kJ/mol, 136.5 calorie/g). Dry ice is non-polar, with a dipole moment of zero, so attractive intermolecular van der Waals forces ...