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Bases water, adding

Iron(III) hydroxide [1309-33-7], FeH02, is a red-brown amorphous material that forms when a strong base is added to a solution of an iron(III) salt. It is also known as hydrated iron(III) oxide. The fully hydrated Fe(OH)3 has not been isolated. The density of the material varies between 3.4-3.9 g/cm, depending on its extent of hydration. It is insoluble in water and alcohol, but redissolves in acid. Iron(III) hydroxide loses water to form Fe203. Iron(III) hydroxide is used as an absorbent in chemical processes, as a pigment, and in abrasives. Salt-free iron(III) hydroxide can be obtained by hydrolysis of iron(III) alkoxides. [Pg.437]

Figure 5 illustrates the type of encapsulation process shown in Figure 4a when the core material is a water-immiscible Hquid. Reactant X, a multihmctional acid chloride, isocyanate, or combination of these reactants, is dissolved in the core material. The resulting mixture is emulsified in an aqueous phase that contains an emulsifier such as partially hydroly2ed poly(vinyl alcohol) or a lignosulfonate. Reactant Y, a multihmctional amine or combination of amines such as ethylenediamine, hexamethylenediamine, or triethylenetetramine, is added to the aqueous phase thereby initiating interfacial polymerisation and formation of a capsule shell. If reactant X is an acid chloride, base is added to the aqueous phase in order to act as an acid scavenger. [Pg.320]

Because almost any diacid can be leaddy converted to the acid chloride, this reaction is quite versatile and several variations have been developed. In the interfacial polymerization method the reaction occurs at the boundary of two phases one contains a solution of the acid chloride in a water-immiscible solvent and the other is a solution of the diamine in water with an inorganic base and a surfactant (48). In the solution method, only one phase is present, which contains a solution of the diamine and diacid chloride. An organic base is added as an acceptor for the hydrogen chloride produced in the reaction (49). Following any of these methods of preparation, the polymer is exposed to water and the acid chloride end is converted to a carboxyhc acid end. However, it is very difficult to remove all traces of chloride from the polymer, even with repeated washings with a strong base. [Pg.224]

One form based on scrubber, another on spiral classifier. They have wash water added to flow essentially horizontally in opposite direction to underflow which is conveyed and resuspended by some form of spiral. [Pg.1779]

In Chapter 13 we dealt with the equilibrium established when a single solute, either a weak acid or a weak base, is added to water. This chapter focuses on the equilibrium established when two different solutes are mixed in water solution. These solutes may be—... [Pg.383]

A solution showing these properties is called a buffer, because it cushions the shock (Le0 the drastic change in pH) that occurs when a strong acid or strong base is added to water. [Pg.383]

C16-0105. Write the equilibrium reaction and equilibrium constant expression for each of the following processes (a) Trimethylamine, (CH3)3 N, a weak base, is added to water, (b) Hydrofluoric acid, HF, a weak acid, is added to water, (c) Solid calcium sulfate, CaSOq, a sparingly soluble salt, is added to water. [Pg.1203]

If a base is added to this solution, the hydrogen ions react with the hydroxide ions to form water. If there are hydroxide ions left over, more ethanoic acid breaks down. Again, because most of the... [Pg.78]

For protonation-dehydration processes, such as trityl cation formation from triphenylcarbinols, equation (24), the water activity has to be included if the formulation of the activity coefficient ratio term is to be the same as that in equation (7), which it should be if linearity in X is to be expected see equation (25). The excess acidity expression in this case becomes equation (26) this is a slightly different formulation from that used previously for these processes,36 the one given here being more rigorous. Molarity-based water activities must be used, or else the standard states for all the species in equation (26) will not be the same, see above. For consistency this means that all values of p/fR listed in the literature will have to have 1.743 added to them, since at present the custom... [Pg.19]

A buffer s job is to keep the pH of a solution from changing very much when either strong acids or strong bases are added to it. To handle the addition of both acids and bases, a buffer contains an acid (to react with added base) and a base (to react with added acid). Take a glass of water (beaker sounds too chemical, and blood sounds too gruesome)... [Pg.261]

Buffer solution—A solution that resists changes in pH even when a strong acid or base is added or when it is diluted with water. [Pg.511]

The view that the clay surface perturbs water molecules at distances well in excess of 10 A has been largely based on measurements of thermodynamic properties of the adsorbed water as a function of the water content of the clay-water mixture. There is an extensive literature on this subject which has been summarized by Low (6.). The properties examined are, among others, the apparent specific heat capacity, the partial specific volume, and the apparent specific expansibility (6.). These measurements were made on samples prepared by mixing predetermined amounts of water and smectite to achieve the desired number of adsorbed water layers. The number of water layers adsorbed on the clay is derived from the amount of water added to the clay and the surface area of the clay. [Pg.42]

For the simultaneous reaction of added OP ester with base, water, and perhydroxyl, we must consider the following minimum reaction set ... [Pg.216]


See other pages where Bases water, adding is mentioned: [Pg.179]    [Pg.137]    [Pg.494]    [Pg.210]    [Pg.272]    [Pg.152]    [Pg.179]    [Pg.299]    [Pg.300]    [Pg.372]    [Pg.61]    [Pg.344]    [Pg.402]    [Pg.326]    [Pg.566]    [Pg.571]    [Pg.25]    [Pg.277]    [Pg.268]    [Pg.179]    [Pg.30]    [Pg.38]    [Pg.92]    [Pg.40]    [Pg.506]    [Pg.33]    [Pg.113]    [Pg.47]    [Pg.359]    [Pg.409]    [Pg.139]    [Pg.64]    [Pg.213]    [Pg.365]    [Pg.209]    [Pg.182]   
See also in sourсe #XX -- [ Pg.737 ]




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Added water

Water-based

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