Density hydroxide solutions

The density of fluorobenzene is about 1 -025 at room temperature it is important to use the correct strength of sodium hydroxide solution in order to obtain a clear separation of the two layers. 

The distillate may contain volatile neutral compounds as well as volatile acids and phenols. Add a slight excess of 10-20 per cent, sodium hydroxide solution to this distillate and distil until the liquid passes over clear or has the density of pure water. The presence of a volatile, water-soluble neutral compound is detected by a periodic determination of the density (see Section XI,2) if the density is definitely less than unity, the presence of a neutral compound may be assumed. Keep this solution Si) for Step 4. 

Other processes have been developed in which the impregnation is accompHshed in one or two steps the most promising is electro deposition directiy from nitrate solutions having pH controlled at 4—5. After electro deposition, the plaques are either cathodicaHy polarized in sodium hydroxide solution or electrochemically formed in sodium hydroxide to eliminate all traces of nitrate. The latter steps must proceed at low current densities to avoid blistering and shedding of the loaded plaques. 

In a copper or iron kettle of 4-I. capacity is placed a solution of 200 g. of d-tartaric acid and 700 g. of sodium hydroxide in 1400 cc. of water. A 12-I. flask through which cold water is run is placed in the mouth of the kettle in order to prevent loss of water vapor, and the mixture is boiled gently over an open flame for four hours. The solution is now transferred to a 12-I. flask or crock and partially neutralized with 1400 cc. of commercial hydrochloric acid (density 1.19). To the still alkaline solution is now added just enough sodium sulfide to precipitate all the iron or copper which has been dissolved from the kettle (Note i). The filtered solution is then just acidified with hydrochloric acid, boiled to expel all hydrogen sulfide, and made very faintly alkaline to phenolphthalein with sodium hydroxide solution. To the hot solution is then added a concentrated solution of 300 g. of anhydrous calcium chloride which causes an immediate precipitation of calcium tff-tartrate and mesotartrate. 

Similar curves determined in 50 Vo sodium hydroxide solution at 60°C show (Fig. 3.46) that the austenitic irons exhibit more noble active dissolution and also lower current densities in the active and passive regions than the ferritic irons the current densities in both regions decrease markedly with increasing nickel content (Fig. 3.47). 

Fig. 3.46 Potential-current density curves in 50% sodium hydroxide solution at 60°C...

In 1899, the nickel-cadmium battery, the first alkaline battery, was invented by a Swedish scientist named Waldmar Jungner. The special feature of this battery was its potential to be recharged. In construction, nickel and cadmium electrodes in a potassium hydroxide solution, it was the first battery to use an alkaline electrolyte. This battery was commercialized in Sweden in 1910 and reached the Unites States in 1946. The first models were robust and had significantly better energy density than lead-acid batteries, but nevertheless, their wide use was limited because of the high costs. 

A bucket containing 25% sodium hydroxide solution was used to catch and neutralise bromine dripping from a leak. Lack of stirring allowed a layer of unreacted bromine to form below the alkali. Many hours later, a violent eruption occurred when the layers were disturbed dining disposal operations. Continuous stirring is essential to prevent stratification of slowly reacting mutually insoluble liquids, especially of such differing densities. 

RECOMMENDED FIELD PROCEDURES Spills must be contained by covering with vermiculite, diatomaceous earth clay, fine sand, sponges, and paper or cloth towels. Decontaminate with copious amounts of aqueous Sodium Hydroxide solution (a minimum 10 wt percent). Scoop up all material and place in a fully removable head drum with a high density polyethylene liner. Cover the contents of the drum with decontaminating solution as above before affixing the drum head. 

What s the density of sodium hydroxide You ve just done a wash with 5-10% sodium hydroxide solution, you ve just read something about finding various layers in the funnel by their densities, and, by this question, you ve just shown that you ve missed the point. Most wash solutions are 5 to 10% active ingredient dissolved in water. This means they are 90 to 95% water. Looking up the density of the solid reagents then, is a waste of time. The density of these solutions is very close to that of water. (10% NaOH has a specific gravity of 1.1089.)... 

YeUow metal face centered cubic crystals lattice constant, a at 25°C 4.0786A density 19.3 g/cm hardness 2.5-3.0 (Mohs), 18.5 (BrineU) melts at 1,064°C vaporizes at 2,856°C electrical resistivity 2.051 microhm-cm at 0°C and 2.255 microhm-cm at 25°C Young s modulus 11.2x10 psi at 20°C (static) Poisson s ratio 0.52 thermal neutron capture cross section 98.8 barns insoluble in almost all single acids or hydroxide solutions dissolves in aqua regia. 

Highly ordered crystalline cellulose has a density as high as 1.63 g cm whereas highly disordered amorphous cellulose has a density as low as 1.47 g cm 3. High-molecular-weight native cellulose, which is insoluble in 17,5% aqueous sodium hydroxide solution, is called alpha cellulose. The fraction that is soluble in 17.5% sodium hydroxide solution but insoluble in 8% solution, is called beta cellulose, and that which is soluble in 8% sodium hydroxide solution is called gamma cellulose. 

The density of a sodium hydroxide solution is 1 1589 g/ml How much does 1 liter of this solution weigh9... 

This work was extended by Elbs and his pupils,1 and the processes were protected by patents.2 Subsequently alcohol was dispensed with and aqueous caustic soda employed. For example, an emulsion of nitrobenzene in 10 per cent, aqueous sodium hydroxide may be reduced with a cathode of lead or nickel in a porous earthenware cell, with a current density of 10-12 amps, per dm.2 An anode of graphite or lead may be employed in an outer containing vessel filled with sodium hydroxide solution or sodium sulphate. Azo- or hydrazobenzene is obtained according to the quantity of electricity passed through, and the azobenzene emulsion can be transformed into benzidine by acidifying the cathode liquor and completing the reduction.4... 

Platinum Monosilicide, PtSi, may be obtained by igniting a mixture of finely divided silicon and platinum sponge at a high temperature. On treating the melt with potassium hydroxide solution, excess of silicon is removed, leaving a residue of monosilicide.5 When recrystallised from fused silver silicide, the latter being removed by extraction with sodium hydroxide and nitric acid in succession, the monosilicide is obtained as prismatic crystals, melting at about 1100° C., and of density 11-63 at 15° C. 

The violet form can also be obtained from some preparations of red phosphorus by the following treatment. The finest particles are washed away in a stream of water until only dark steel-blue particles are left these are boiled with 30 per cent, sodium hydroxide solution, washed again, boiled with 5 per cent, nitric acid, washed with hot and cold water, then with absolute alcohol and ether, and allowed to stand until dry in a vacuum desiccator with concentrated sulphuric acid.2 The density of this preparation is about 2-2 (2T8 to 2-23). 

A metal hydride battery similar to the nickel-cadmium battery has been developed by Sharp corporation. The battery is shaped in the form of a button of 20 mm diameter and can give 1.2 V. The anode in the battery is made of La-Ni-Sn alloy hydride, and the cathode is nickel oxide. Potassium hydroxide solution in polyamide-resin is the electrolyte. The battery exhibits high energy density (i.e.) 1.5 to 2.0 times that of the Ni-Cd battery, good cycling life and superior low temperature behaviours. 

The action on sulphur of ammonium hydroxide solution of density 0-888 is similar to that of a concentrated aqueous solution of sodium or potassium hydroxide (pp. Ill and 171). 

A substance having a composition corresponding to the diliydrate, Fe203.2H20, is obtained by dissolving reduced iron in hot, diluted sulphuric acid and heating until the acid begins to fume and the iron is transformed into a faintly red, crystalline powder. The acid is poured off and the precipitate shaken with sodium hydroxide solution and finally washed with water. The substance is formed as brownish plates of density 3 234 at 15° C.7... 

The equilibrium hole concentration can be increased by raising the temperature of the semiconductor. Uhlir (7) found that the temperature variation of the saturation current density across the barrier between anodic n-type germanium and 10% potassium hydroxide solution is quite like that of a p-n junction. About a tenfold increase in the saturation current density is obtained for each 30° C rise in temperature as shown in Fig. 2. 

For example, when 5,8-dimethyl-[l,2,4]triazolo[4,3- ]pyrazine was refluxed with 10% sodium hydroxide solution for 60 hours, a 20% yield of the isomeric 5,8-dimethyl-[l,2,4]triazolo[l,5-a]pyrazine was obtained. No rearrangement occurred in acid or under the influence of heat (68JHC485). The poor yield obtained in this isomerization may be due to two factors (i) electronic deactivation and steric crowding caused by the 5-methyl group and/or (ii) the great tt-electron density associated with C-5 (as determined by HMO calculations) for [l,2,4]triazolo[4,3-a]pyrazines in general (68JHC485). 

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