Solution Concentration Normality Optional

10 Given an equation for a neutralization reaction, state the number of equivalents of acid or base per mole and calculate the equivalent mass of the acid or base. 

11 Given two of the following, calculate the third equivalents of acid or base (or data from which they may be found), volume of solution, normality. 

A particularly convenient concentration in routine analytical work is normality, N, the number of equivalents, eq, per liter of solution. (The equivalent will be defined shortly.) The defining equation is 

If a solution contains 0.755 equivalent of phosphoric acid per liter, we identify it as 0.755 N H3PO4. In words it is point seven-five-five normal phosphoric acid. In a calculation setup we would write 0.755 eq H3PO4/L.  

The defining equation for normality is very similar to the equation for molarity (Equation 16.2). Many of the calculations are similar, too. But to understand the difference, we must see what an equivalent is. 

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Solution Concentration Molality (Optional) Solution Concentration Normality (Optional) Solution Concentration ... 

Resin adsorption. The resin adsorption is a good option for the selective removal of waste. This technique is normally used for the removal of ther-molabile organic solutes from aqueous waste streams. The solute concentration of solution ranges fiwm 1 to 8 percent. Moreover, synthetic cationic and anionic resins may be used to remove a hydrophobic, hydrophihc, or neutral solute, which can also be recovered by chemical methods. These resins are also used with a high concentration of dissolved inorganic salts in the waste stream. Their appUcations include phenol, fat, organics, and color removal from wastewater. They can be apphed for the removal of pesticides, carcinogens, and chlorofluoro compounds. 

One of the major goals of this endeavor was to solubilize the normally intractable polyimides by the incorporation of siloxane segments, and, optionally, by solution imidization. Solubilities of a series of siloxane-modified polyimide copolymers were evaluated in a variety of solvents as indicated in Table I. Copolymer solubility was found to be a function of the siloxane oligomer concentration... 

Standards for the analysis may be prepared from organometallic standards, analysed samples or the NBS (GM-5) Heavy Oil Standard. The most satisfactory results are likely to be obtained using the second or third options. The sensitivity available is critically dependent on the electrothermal device to be used. This and the size of aliquot chosen for injection into the atomiser (normally 5—100 pi) will determine the selection of the concentration ranges chosen for the standards. Refer to the manufacturers information on Ni and V sensitivity and linear range and prepare calibration standards accordingly. Always prepare a blank solution and at least three standards to cover the chosen range. 

Typically conventional polymer isolation procedures do not permit product isolation within a specific concentration region however, under certain conditions the operation of freeze drying ionomer solutions would be expected to offer this option. Thus, freeze drying of S-PS at two different concentrations (0.3 and A.O weight percent polymer) from appropriate solvents should offer two different polymer species. This hypothesis, of course, assumes that once solutions of this polymer are frozen, the polymer conformations will be "locked in" at those concentrations, or the normal changes which might occur under other conditions of polymer isolation will be minimized. 

Another option for secondary smelters is to desulfurize the battery paste prior to smelting. Chemical desulfurization, however, is dependent on physical mixing conditions and temperature. Chemical desulfurization is achieved by adding a concentrated sodium carbonate solution to an agitated mix of battery paste sludge to convert the lead sulfates to lead carbonates. Complete conversion of lead sulfate to lead carbonate eliminates sulfur in the furnace feed material and sulfur dioxide in the exhaust gases. Complete desulfurization is, however, rarely achieved under normal industrial conditions. 

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