Bottle hydration

Many studies have been reported on the hydration of C3S or p-CjS in aqueous suspensions, often termed bottle hydration . If the reaction is prolonged, so that no unreacted starting material remains, and the w/s ratio is sufficiently high that the Ca/Si ratio of the product is below about 1.5, the... 

For this preparation, it is particularly necessary that the sodium acetate should be free from traces of water. The anhydrous material can be prepared by gently heating the hydrated salt (CHsCOONa,3HjO) in an esaporating-basin over a small Bunsen flame. The salt dissolves in its water of ciystallisation and resolidifies as this water is driven off further heating then causes the anhydrous material to melt. Stir the molten anhydrous material to avoid charring, and then allow it to cool in a desiccator. Powder the cold material rapidly in a mortar, and bottle without delay. 

Dry A.R. hydrated cadmium chloride to constant weight at 110° grind finely, dry again for 2-3 hours at 110° and then place in a screw-capped bottle and keep in a desiccator over calcium chloride. 

Brom-benzol, n. bromobenzene. calcium, n. calcium bromide, -cyan, n. cyanogen bromide, bromocyanogen. -dampf, tn. bromine vapor, -eisen, n. iron bromide, -fiasche, /. bromine bottle, -fluor, n. bromine fluoride, -gehalt, tn. bromine content, -gold, n. gold bromide, -goldkalium, n. potassium auri-bromide, potassium bromoaurate. bromhaltig, a. contaim ng bromine, Brom-hydrat, n. hydrobromide bromine hydrate. -hydrin, n. bromohydrin. 

When dried in an oven, hydrated silica loses its water and becomes a desiccant (a substance that attracts water from the air). You find little packets of silica gel crystals in containers whose contents would be damaged by condensing moisture, such as vitamin bottles, consumer electronics, pepperoni, or leather products. 

Acetylcyclohexanone. Method A. Place a mixture of 24-6 g. of cyclohexanone (regenerated from the bisulphite compound) and 61 g. (47 5 ml.) of A.R. acetic anhydride in a 500 ml. three-necked flask, fitted with an efficient sealed stirrer, a gas inlet tube reaching to within 1-2 cm. of the surface of the liquid combined with a thermometer immersed in the liquid (compare Fig. II, 7, 12, 6), and (in the third neck) a gas outlet tube leading to an alkali or water trap (Fig. II, 8, 1). Immerse the flask in a bath of Dry Ice - acetone, stir the mixture vigorously and pass commercial boron trifluoride (via an empty wash bottle and then through 95 per cent, sulphuric acid) as fast as possible (10-20 minutes) until the mixture, kept at 0-10°, is saturated (copious evolution of white fumes when the outlet tube is disconnected from the trap). Replace the Dry Ice-acetone bath by an ice bath and pass the gas in at a slower rate to ensure maximum absorption. Stir for 3 6 hours whilst allowing the ice bath to attain room temperature slowly. Pour the reaction mixture into a solution of 136 g. of hydrated sodium acetate in 250 ml. of water, reflux for 60 minutes (or until the boron fluoride complexes are hydrolysed), cool in ice and extract with three 50 ml. portions of petroleum ether, b.p. 40-60° (1), wash the combined extracts free of acid with sodium bicarbonate solution, dry over anhydrous calcium sulphate, remove the solvent by... 

A laboratory oven (Note 1) is equipped with as many clay plates or enameled pie plates or trays as it will accommodate and is adjusted to operate at 98-99° (Notes 2 and 3). When the temperature has become constant the plates are removed, rapidly covered with a layer (not over 3-4 mm. deep) of pulverized (Notfe 4) hydrated oxalic acid, and then quickly replaced in the oven. The temperature will drop slightly for a few minutes (Note 5). After the oven has regained the temperature for which it was adjusted, it is heated for two hours longer at this temperature. The product is then removed, crushed if slightly caked, and quickly bottled. The yield from 100 g. of hydrated oxalic acid is 69-70 g. (96-98 per cent of the theoretical amount) (Note 6). The product is 99.5-100 per cent pure, as indicated by titration with standard alkali. 

A) Purification of Citral.—In a 4-1. bottle are placed 1 1. of water, 1 kg. of crushed ice, 450 g. of anhydrous sodium sulfite (or an equivalent amount of hydrated sodium sulfite), 320 g. of sodium bicarbonate, and 270 g. (304 cc., 1.78 moles) of commercial citral (Note 1). A tightly fitting stopper is securely wired into place, and the bottle is shaken thoroughly for five to six hours. The solution, which contains very little unchanged citral, is extracted twice with 300-cc. portions of ether (Note 2). 

About half the propane produced annually in the U.S. is used as a domestic and industrial fuel. When it is used as a fuel, propane is not separated from the related compounds, butane, ethane, and propylene. Butane, with boiling point -0.5 °C (31.1 °F), however, reduces somewhat the rate of evaporation of the liquid mixture. Propane forms a solid hydrate at low temperatures, and this causes great inconvenience when a blockage occurs in a natural-gas line. Propane is used also as so-called bottled gas, as a motor fuel, as a refrigerant, as a low-temperature solvent, and as a source of propylene and ethylene. 

Strength Rescue, curfew and evacuation operations were initially planned for a 7-day period. Issues identified and addressed included food/hydration/shelter/sanitation bar-ricades/shift rotation. ADPS and ACSO provided hurricane stock of bottled water for responders. 

Get some of your eluent and prewet the adsorbant somewhat. For about 10 g of adsorbant, start with 3 - 5 g of the liquid eluent. (Oh. Did anyone ever tell you, you can weigh liquids directly, just like solids ) Now add the eluent to the adsorbant and mix like mad. You can see the advantage of a screw-cap bottle over an open beaker. The powder can t fly out of a closed bottle. Do not add too much eluent You only want to precondition the adsorbant so that you don t get bubbling in the column from the heat of hydration released when you eventually run the experiment. 

Skin contact of the powder can cause severe irritation. Mixing the powder form of the compound with water can produce explosive reactions with liberation of large quantities of heat. The reaction occurs after a few minutes delay (Mellor, J. W. 1941. Comprehensive Treatise on Inorganic and Theoretical Chemistry, Vol. 3, pp. 673. London Longmans Green). The presence of moisture in storage containers or bottles may produce an explosion hazard. Hydration of granular lumps, however, is slow and smooth. 

There are several other important considerations in choosing starting materials. First, the purity must be sufficient. A material that is 99% pure is 1% other compounds. Impurities may have profound effects on the properties of materials such as lowering the Tc of a superconductor. Also, the composition indicated on the label may not be what is found in the bottle. For instance, La2Os readily converts to La(OH)s upon exposure to moisture, and a number of hydrates gain or lose water depending on the ambient humidity. Such... 

When the dissociation pressure of the hydrate is small, as with CuS04-5H20, the drying of the salt presents no difficulty. Even when there is some disposition toward efflorescence, the crystals may be dried on paper in the usual way if they are stirred frequently and watched closely. At the first sign of efflorescence they should be bottled up. In many cases, however, some crystals will begin to effloresce while others are still wet with mother liquor. In such an event it is best to proceed as follows ... 

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