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KOH solutions

Absorbing each constituent preferentially by means of a reagent, e.g. CO2 in KOH solution, CO in acid or alkaline CuCl. [Pg.186]

SNG Substitute natural gas. soaps Sodium and potassium salts of fatty acids, particularly stearic, palmitic and oleic acids. Animal and vegetable oils and fats, from which soaps are prepared, consist essentially of the glyceryl esters of these acids. In soap manufacture the oil or fat is heated with dilute NaOH (less frequently KOH) solution in large vats. When hydrolysis is complete the soap is salted out , or precipitated from solution by addition of NaCl. The soap is then treated, as required, with perfumes, etc. and made into tablets. [Pg.362]

Weigh out accurately about 2-5 g. of pure powdered succinic acid, transfer to a 100 ml. graduated flask, dissolve in distilled water, make the solution up to the graduation mark and mix well. Now, by means of a pipette, transfer 25 ml. of the solution to a 150 ml. conical flask, add a drop of phenolphthalein solution and titrate with A/ 2 NaOH or KOH solution to obtain consistent results. [Pg.448]

So now that we have all the reagents out of the way let s see how the reaction proceeds. There s the clear- yellow "safrole" sitting in the bottom if the flask and the clear saturated KOH solution is dumped in. The solution is heated to reflux etc. and yes, some brown byproducts and destruction artifacts will appear. Especially if the safrole is not pure. These byproducts should be expected to some extent because concentrated basic (OH) solutions can be as nasty as concentrated acidic solutions. One is mindful that KOH is less intrusive towards the delicate methylenedioxy ring structure of the safrole/isosafrole molecule. [Pg.40]

Potassium pyrogaiiate (oxygen in gas analysis) weigh out 5 g of pyrogallol (pyrogallic acid), and pour upon it 100 mL of a KOH solution. If the gas contains less than 28% of oxygen, the KOH solution should be 500 g KOH in a liter of water if there is more than 28% of oxygen in the gas, the KOH solution should be 120 g of KOH in 100 mL of water. [Pg.1195]

GeneraHy the systems operate in the gas phase, but a system in which the superoxides react with Hquid-phase water and absorb CO2 in the resultant KOH solution has been buHt (25). The RQ is fixed at 0.67. [Pg.487]

Fig. 8. Boiling and freezing temperatures of KOH solutions (33). The boiling point curve assumes a pressure of 101.3 kPa (760 mm Hg). Fig. 8. Boiling and freezing temperatures of KOH solutions (33). The boiling point curve assumes a pressure of 101.3 kPa (760 mm Hg).
The Van Krevelen-Hoftyzer relationship was tested experimentally for the second-order system in which CO9 reacts with either NaOH or KOH solutions by Nijsing et al. [Chem. Eng. ScL, 10, 88 (1959)]. Nijsing s results for the NaOH system are shown in Fig. 14-15 and are in excellent agreement with the second-order-reaction theory. Indeed, these experimental results can be described very well by Eqs. (14-80) and (14-81) when values of V = 2 and T)JT = 0.64 are employed in the equations. [Pg.1368]

The polarization cell is an electrochemical component in which nickel or stainless steel electrodes are immersed in 50% KOH solution [9]. With ac, the... [Pg.340]

The pH of 1.2 liters of filtrate containing 3.B mg/ml of cytidine diphosphate choline, obtained by removing solid matters from the culturing liquor, was adjusted to a pH of B.5 with a 0.5N KOH solution. The filtrate was passed through a column of strongly basic anion exchange resin, Dowex 1 x 2 (formic acid type). After washing the resin with water, a formic acid... [Pg.348]

PbOj has a low overpotential for the liberation of oxygen from and KOH solutions, and for chlorine . [Pg.725]

Tin when made anodic shows passive behaviour as surface films are built up but slow dissolution of tin may persist in some solutions and transpassive dissolution may occur in strongly alkaline solutions. Some details have been published for phosphoric acid with readily obtained passivity, and sulphuric acid " for which activity is more persistent, but most interest has been shown in the effects in alkaline solutions. For galvanostatic polarisation in sodium borate and in sodium carbonate solutions at 1 x 10" -50 X 10" A/cm, simultaneous dissolution of tin as stannite ions and formation of a layer of SnO occurs until a critical potential is reached, at which a different oxide or hydroxide (possibly SnOj) is formed and dissolution ceases. Finally oxygen is evolved from the passive metal. The nature of the surface films formed in KOH solutions up to 7 m and other alkaline solutions has also been examined. [Pg.806]

Sodium hydroxide (NaOH) and potassium hydroxide (KOH) solutions do not dissolve tantalum, but tend to destroy the metal by formation of successive layers of surface scale. The rate of the destruction increases with concentration and temperature. Damage to tantalum equipment has been experienced unexpectedly when strong alkaline solutions are used during cleaning and maintenance. [Pg.896]

Hydrogen Measurement Side filked with KOH solution surface of specimen may be plated with Palladium. [Pg.1233]

A student prepares 455 mL of a KOH solution, but neglects to write down the mass of KOH added. His TA suggests that he take the pH of the solution. The pH is 13.33. How many grams of KOH were added ... [Pg.380]

An important reaction of fats is the reverse of ester formation. They hydrolyze, or react with water, just as disaccharides do. Usually hydrolysis is carried out in aqueous Ca(OH)2, NaOH, or KOH solution. Because of long use in the preparation of soap from fats, the alkaline hydrolysis reaction (6) is called saponification. [Pg.426]

Figure 6. Static potential of / - Mn02 after heating in air between 100 and 400 °C. All the samples were heated at each temperature for 2 h and cooled quickly to 25 °C, The potential was measured in 1 mol L 1 KOH solution. Point "a" and b" are the values obtained with the P - Mn02 samples which were cooled slowly (allowing samples to reach room temperature overnight). Figure 6. Static potential of / - Mn02 after heating in air between 100 and 400 °C. All the samples were heated at each temperature for 2 h and cooled quickly to 25 °C, The potential was measured in 1 mol L 1 KOH solution. Point "a" and b" are the values obtained with the P - Mn02 samples which were cooled slowly (allowing samples to reach room temperature overnight).
Since the pH change //(ApH) is practically zero for the discharge in 9molL KOH solution, we can assume that 77a + 7/t (solid) is the same for the two solutions (9molL l KOH and 25% ZnCl2). Therefore, the difference in the polarization values (in Tables 1 and 2) is... [Pg.119]

Table 2. Open-circuit voltage (OCV) and polarization (P) at 1.00 mA per 100 mg sample in 9 mol L1 KOH solution ... Table 2. Open-circuit voltage (OCV) and polarization (P) at 1.00 mA per 100 mg sample in 9 mol L1 KOH solution ...
Delmas and his co-workers have done extensive work on pyroaurite-type materials which has recently been reviewed [73], In addition to precipitation methods, they have prepared the materials by mild oxidative hydrolysis of nickelates that were prepared by thermal methods similar to those used for the preparation of LiNiOz [74]. A cobalt-substituted material NaCoA ( Ni( A02) was prepared by the reaction of Na20, Co304 and NiO at 800 °C under a stream of oxygen. The material was then treated with a 10 molL-1 NaCIO +4 molL 1 KOH solution for 15h to form the oxidized y -oxyhydroxide. The pyroau-... [Pg.144]

FIG. 5 Influence of the alkyl chain on the alkali stability of some alkyl ether carboxy-lates. 1% surfactant in different KOH solutions. (From Refs. 61 and 64.)... [Pg.334]

Figure 6.8. Example of rule G3 (volcano-type behaviour) Effect of Ph2(=Pd) (a), Po2 (=Pa) (b) and of potential UWR and AO (c) on the rate of H2 oxidation on Pt /graphite (a and b) and Pt/black (c) in aqueous 0.1 M KOH solutions.72,73 Note that under the pH2, Po2 conditions of Fig. 6.7c the open-circuit rate is positive order in H2 (Fig. 6.8a) and negative order in 02 (Fig. 6,8b) and that the orders are reversed with the applied positive potential (Uwr=1 -2 V). At this potential the rate passes through its maximum (volcano) value (Fig. 6.8c). Reprinted with permission from McMillan Magazines Ltd (ref. 72) and from the American Chemical Society (ref. 73). Figure 6.8. Example of rule G3 (volcano-type behaviour) Effect of Ph2(=Pd) (a), Po2 (=Pa) (b) and of potential UWR and AO (c) on the rate of H2 oxidation on Pt /graphite (a and b) and Pt/black (c) in aqueous 0.1 M KOH solutions.72,73 Note that under the pH2, Po2 conditions of Fig. 6.7c the open-circuit rate is positive order in H2 (Fig. 6.8a) and negative order in 02 (Fig. 6,8b) and that the orders are reversed with the applied positive potential (Uwr=1 -2 V). At this potential the rate passes through its maximum (volcano) value (Fig. 6.8c). Reprinted with permission from McMillan Magazines Ltd (ref. 72) and from the American Chemical Society (ref. 73).
A student added solid K,0 to a 500.0 mL volumetric flask, which was then filled with water, resulting in 500.0 mL of KOH solution. 10.0 mL of the solution was then transferred to another volumetric flask and diluted to... [Pg.558]

The hydrolytic depolymerisation of PETP in stirred potassium hydroxide solution was investigated. It was found that the depolymerisation reaction rate in a KOH solution was much more rapid than that in a neutral water solution. The correlation between the yield of product and the conversion of PETP showed that the main alkaline hydrolysis of PETP linkages was through a mechanism of chain-end scission. The result of kinetic analysis showed that the reaction rate was first order with respect to the concentration of KOH and to the concentration of PETP solids, respectively. This indicated that the ester linkages in PETP were hydrolysed sequentially. The activation energy for the depolymerisation of solid PETP in a KOH solution was 69 kJ/mol and the Arrhenius constant was 419 L/min/sq cm. 21 refs. [Pg.40]

The answer to this problem was in situ generation of the free phenylbutadiyne under standard Pd-coupling conditions [66]. Addition of a few milliliters of a concentrated KOH solution provided the bis-coupled product in 71 % yield. Desilylation and use of high dilution conditions in the oxidative coupling reaction gave 1 as the sole product in moderate yield. Compound 1 was poorly soluble in common organic solvents nevertheless, all of the spectral data (NMR, IR, UV,MS) supported the assigned structure. The minimal solubility of the product was no-doubt responsible for the low isolated yield. [Pg.109]


See other pages where KOH solutions is mentioned: [Pg.325]    [Pg.325]    [Pg.325]    [Pg.448]    [Pg.40]    [Pg.504]    [Pg.534]    [Pg.534]    [Pg.548]    [Pg.455]    [Pg.63]    [Pg.799]    [Pg.803]    [Pg.377]    [Pg.445]    [Pg.115]    [Pg.118]    [Pg.121]    [Pg.121]    [Pg.137]    [Pg.144]    [Pg.201]    [Pg.555]    [Pg.114]    [Pg.476]    [Pg.255]   
See also in sourсe #XX -- [ Pg.269 , Pg.270 ]




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