Sublimation water

Phenocoll hydrochloride (4-ethoxyaniline, p-phenetidine HCI) pK 5.20. Crystd from water. Sublimes in vacuo. 

After 3 days, cooling of the shelves was terminated and the temperature of the bones rose to -15 °C. The operation pressure in the plant was always 0.1 mbar or less. The first 3 days can be saved, since at Tpr -35 °C / s is approx. 0.2 mbar. The amount of water sublimated during these 3 days was small compared with the amount sublimated thereafter at Tpr -15 °C, since ps 1,5 mbar. From the third day on, seven times more water/unit time can be sublimated than in the previous days. Therefore it is recommended to rise from the beginning to -15 °C. The ice temperature at the sublimation front Tkc, established under these conditions, can be measured by BTM, as shown in Section 1.2.1. 

The frozen water sublimed, moving directly from a solid to a gaseous stale. Although this process occurs slowly at the temperatures and pressures found within normal household freezers, it does occur. Try it. 

O.IM HCI). Crystd from water. Sublimes below its melting point in a vacuum. 

Indazole [271-44-3] M 118.1, m 147 . Crystd from water, sublimed under a vacuum, then pet ether (b 60-80°). 

Rates of Enolization Reactions. For a better understanding of the transformation and oxidation reactions of reducing sugars, methods have been developed to measure the primary rates of enolization (18). One of these methods depends on the rate at which tritium ions are released from aldoses-2- to the solvent. This is measured by separation of the water-, sublimation, and radiochemical assay of the water as the reaction proceeds. The rate constant is calculated from the first-order equation ... 

Yield.—50% theoretical (9 gms.). Yellow needles sweet odour insoluble in water sublimes when heated M.P. 198°. (A., 274, 71.)... 

Yield.—90% theoretical (22 gms.). Yellow leaflets characteristic odour insoluble in water sublimes on heating. (B., 36, 4390.)... 

Line G-H shows that when the solid form (ice) passes directly into the vapor phase without first becoming a liquid, then sublimation is said to occur. Water sublimes below 32°F. As an example, everyone has seen frost disappear in the winter, even though the thermometer might have read 25°F. 

Lyophilization employs sub-zero temperatures in combination with very low pressure to withdraw water from the protein solution typical values would be -80 °C and 1-3 mbar. In these conditions, as the water phase diagram reveals, water sublimes, leaving a fluffy porous enzyme powder. As typical run times are on the order of a day, lyophilization is not the method of choice for large-scale enzyme drying operations. On a laboratory scale, however, lyophilization is a very effective method. 

Along the line AB, solid is in equilibrium with vapor. If the pressure is decreased below the line AB, the solid will sublime. This relationship is the basis of freeze-drying foods, such as those shown in Figure 25. The food is frozen, and then a vacuum is applied. Water sublimes, which dehydrates the food very quickly. The food breaks down less when water is removed at the low temperature than when water evaporates at normal temperatures. 

Figure 3.9 also shows the p-T conditions at which ice (in its common form) and water vapor are in equilibrium. When the solid passes directly into the vapor phase without first melting to become a liquid (line J-K as opposed to line L-M-N-0), it is said to sublime. Iodine crystals do this at room temperature water sublimes only below 0 C, as when the frost disappears in the winter when the thermometer reads — 6 C. 

Properties Colorless crystals camphorlike odor. D 0.838, mp 11C, bp 196-197C, flash p 165F (74C) (COC). Soluble in alcohol, ether, and benzene insoluble in water sublimes and is volatile with steam. Combustible. 

Crystalhse indazole from water, sublime it in vacuo, then recrystallise it from pet ether (b 60-80°). The picrate crystallises from Et20 with m 136°. [Ainsworth Org Synth Coll Vol IV 536 1963, Beilstein 23 III/IV 1055, 23/6 V 156.]... 

Do you believe compounds other than water sublimed In commercial processes, they often add flavor components to the dried products. 

Rectangular plates from acetone water- Sublimes in high vacuum between 140 and 170. (Anhydr base mp 189 ) [a]jj —77 (c = 1,6 in methanol). So) in acetone, ethyl acetate. Alcoholic solns darken and acquire a reddish color Hemihydr te crystals from ethyl acetate, mp 162-164. [ )ff —79° (c = 1.08 in ethyl aoetate). 

Hydrochloride, C,2HwNj,HCl, rosettes of needles from ethanol + 20% HC] in water, sublimes at 120-1 3CP. 

E.Z)-Form, isochavfcinic acid. Yellow crystals from methanol/water, sublimes as needles, mp 134-136 (Lohaus, Gall) 143 (Grewe). uv max (methanol) 335 nm (< 14.500). Sol in methanol, benzene. 

Vaporization of water Solution of benzoic acid in water Sublimation of NH4SH Combination of BaC + 2IL,0. Dissociation of N204. Precipitation of AgCl 10100 6700 21560 3815 12900 15992 10296 6500 21640 3830 12500 15850... 

CHEMICAL PROPERTIES contains approximately 36% active chlorine dry crystals, containing 77.6% available chlorine, may be stored without losing much available chlorine will suffer a loss of 1.5% chlorine after 14 weeks at 60 C (140 F) liberates hypochlorous acid on contact with water, and, in particular, hot water sublimes approximately at 100 C (212 F) forms nitrogen chloride at pH 9 FP (174.4°C, 346 F) LFL/UFL (unknown) AT (unknown) HC (information not found in the literature). 

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