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Potassium charge

The resonant level model readily explains the change in work function associated with chemisorption. It is well known that alkali atoms such as potassium lower the work function of the substrate, whereas electronegative atoms such as chlorine increase the work function [2,8,19]. Figure A. 10 indicates that potassium charges positively and chlorine negatively when adsorbed on jellium. Remember that the surface contribution to the work function is caused by... [Pg.308]

X-ray diffraction and wet chemical analysis of the ash from the multiple catalyst runs revealed the presence of potassium carbonate and its IY2 hydrate. This was the initial form of the potassium charged to the system. Material balances on the potassium carbonate showed that although the majority of this compound ends up in the ash, some of it is lost to the system. [Pg.223]

We will focus on one experimental study here. Monovoukas and Cast studied polystyrene particles witli a = 61 nm in potassium chloride solutions [86]. They obtained a very good agreement between tlieir observations and tire predicted Yukawa phase diagram (see figure C2.6.9). In order to make tire comparison tliey rescaled the particle charges according to Alexander et al [43] (see also [82]). At high electrolyte concentrations, tire particle interactions tend to hard-sphere behaviour (see section C2.6.4) and tire phase transition shifts to volume fractions around 0.5 [88]. [Pg.2687]

The ability of living organisms to differentiate between the chemically similar sodium and potassium ions must depend upon some difference between these two ions in aqueous solution. Essentially, this difference is one of size of the hydrated ions, which in turn means a difference in the force of electrostatic (coulombic) attraction between the hydrated cation and a negatively-charged site in the cell membrane thus a site may be able to accept the smaller ion Na (aq) and reject the larger K (aq). This same mechanism of selectivity operates in other ion-selection processes, notably in ion-exchange resins. [Pg.124]

The flask was charged with 2.0 mol of dry, freshly distilled (note 1) methyl propargyl ether (VIII-6, Exp. 7), potassium iert.-butoxide (note 2) (5 g) was added with stirring and the mixture was heated under reflux. The reaction was... [Pg.92]

Phthalimide with a of 8 3 can be quantitatively converted to its potassium salt with potassium hydroxide The potassium salt of phthalimide has a negatively charged nitrogen atom which acts as a nucleophile toward primary alkyl halides m a bimolecu lar nucleophilic substitution (Sn2) process... [Pg.930]

Flame-Retardant Treatments For Wool. Although wool is regarded as a naturally flame-resistant fiber, for certain appHcations, such as use in aircraft, it is necessary to meet more stringent requirements. The Zirpro process, developed for this purpose (122,123), is based on the exhaustion of negatively charged zirconium and titanium complexes on wool fiber under acidic conditions. Specific agents used for this purpose are potassium hexafluoro zirconate [16923-95-8] [16923-95-8] K ZrF, and potassium hexafluoro titanate [16919-27-0], K TiF. Various modifications of this process have been... [Pg.490]

Potassium bifluoride, KE HE, is used as a raw material to charge the cells initially and for makeup when cells are rebuilt. A newly charged cell requires about 1400 kg KE HE. Overall consumption of KE HE per kilogram of fluorine generated is small. Gommercial-grade flake potassium bifluoride is acceptable. Its specifications are... [Pg.128]

A number of cationic muds have been developed and used. These ate formulated around quaternary amines or positively charged polymers (108,109). The polymer in some iastances may be a cationic polyacrylamide. Poly(dimethylarnine-fi9-epichloiohydrin) is another material that has been used successfiiUy for drilling shale formations (110,111). Some of these additives may requite a salt such as sodium or potassium chloride for best results. [Pg.182]

Cyanide Iron Blues. Cyanide iron blue, also known as Pmssian blue, is one of the oldest industrially produced, inorganic pigments. Chemically, cyanide iron blues are based on the [Fe " Fe (CN) ] anion. The charge is balanced by sodium, potassium, or ammonium cations. Modem... [Pg.14]

There are a considerable number of stable crystalline salts of the ammonium ion [14798-03-9] NH. Several are of commercial importance because of large scale consumption in fertiliser and industrial markets. The ammonium ion is about the same size as the potassium and mbidium ions, so these salts are often isomorphous and have similar solubiUty in water. Compounds in which the ammonium ion is combined with a large, uninegative anion are usually the most stable. Ammonium salts containing a small, highly charged anion generally dissociate easily into ammonia (qv) and the free acid (1). At about 300°C most simple ammonium salts volatilize with dissociation, for example... [Pg.362]


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