Search results
Results From The WOW.Com Content Network
Camphor being purified on a sublimation apparatus. Note the white purified camphor on the cold finger, and the dark-brown crude product. Dark green crystals of nickelocene, freshly sublimed on the cold finger of the sublimation apparatus.
Dark green crystals of nickelocene, sublimed and freshly deposited on a cold finger Sublimation of iodine. 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]
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 gallium nitride).
Cold finger used in sublimation.The raw product (6) is in the bottom of the outer tube (4) which is heated (7) while under vacuum (through side-arm 3). The sublimated material collects (5) on the cold finger proper, cooled by a coolant (blue) circulated through ports 1 and 2.
Camphor (/ ˈ k æ m f ər /) is a waxy, colorless solid with a strong aroma. [5] It is classified as a terpenoid and a cyclic ketone.It is found in the wood of the camphor laurel (Cinnamomum camphora), a large evergreen tree found in East Asia; and in the kapur tree (Dryobalanops sp.), a tall timber tree from South East Asia.
In thermodynamics, an exothermic process (from Ancient Greek έξω (éxō) 'outward' and θερμικός (thermikós) 'thermal') [1] is a thermodynamic process or reaction that releases energy from the system to its surroundings, [2] usually in the form of heat, but also in a form of light (e.g. a spark, flame, or flash), electricity (e.g. a ...
Transport reactions are classified according to the thermodynamics of the reaction between the solid and the transporting agent. When the reaction is exothermic, then the solid of interest is transported from the cooler end (which can be quite hot) of the reactor to a hot end, where the equilibrium constant is less favorable and the crystals grow.
Menthol and camphor, both solids at room temperature, form a eutectic that is a liquid at room temperature in the following proportions: 8:2, 7:3, 6:4, and 5:5. Both substances are common ingredients in pharmacy extemporaneous preparations.