Aqueous reactions molarity

Dissolve mono(lactosylamido) mono(succinimidyl)suberate in dry DMF to prepare a concentrated solution from which an aliquot may be taken and added to a final aqueous reaction medium. The compound is extremely soluble in DMF, and solutions of 100 mg/ ml may be prepared. The use of dry solvent is essential to prevent hydrolysis of the NHS ester. However, make only enough of this stock solution so that a small amount added to the protein reaction will provide the appropriate molar excess desired for the modification reaction. 

Add a quantity of the DyLight 649 dye to the dendrimer solution to provide at least a 1.25-fold molar excess of dye over the amount of dendrimer present (for nonaqueous reactions) or a 6-15-fold molar excess for aqueous reactions. Mix well to dissolve. The optimal amount of dye added should be determined experimentally by preparing a series of conjugates using different molar ratios of dye-to-dendrimer. 

The NHS ester end of NHS-LC-biotin reacts with amine groups in proteins and other molecules to form stable amide bond derivatives (Figure 11.4). Optimal reaction conditions are at a pH of 7-9, but the higher the pH the greater will be the hydrolysis rate of the ester. Avoid amine-containing buffers which will compete in the acylation reaction. NHS-LC-biotin is insoluble in aqueous reaction conditions and must be solubilized in organic solvent prior to the addition of a small quantity to a buffered reaction. Preparation of concentrated stock solutions may be done in DMF or DMSO. Nonaqueous reactions also may be done with this reagent for the modification of molecules insoluble in water. The molar ratio of NHS-LC-biotin to a... 

Add 10—40 ul of the SATA stock solution per ml of lmg/ml antibody solution. This will result in a molar excess of approximately 12- to 50-fold of SATA over the antibody concentration (for an initial antibody concentration of lmg/ml). A 12-fold molar excess works well, but higher levels of SATA incorporation will potentially result in more maleimide-activated enzyme molecules able to couple to each thiolated antibody molecule. For higher concentrations of antibody in the reaction medium, proportionally increase the amount of SATA addition however do not exceed 10 percent DMF in the aqueous reaction medium. 

Calculate the reactor volumes required to process 100 liter/min of 3 molar A in the aqueous reaction A -4 2B for PFTR and CSTR reactors. 

Although AV visibly depends on the polarity of the solvent, this is not actually the case for AV. The reaction volume based on partial molar volumes is almost constant (unfortunately, it was not possible to determine AV for the aqueous reaction due to the absence of reproducibility). The ratio 0 = AV /AV decreases with increasing polarity of the medium whereas the virtual volume of the transition state increases. These values refer to electrostriction reflected by AV which may have importance, particularly for the least polar solvents. In this case, [AV > AV, a seemingly surprising result. However, if AVJ is taken into account, which may represent 20-25 % of the overall value of AV, 0 would be slightly <1 in agree-... 

Consider the equilibrium Na20(s) -I- 802(g) Na2S03(s). (a) Write the equihbrium-constant expression for this reaction in terms of partial pressures, (b) All the compounds in this reaction are soluble in water. Rewrite the equilibrium-constant expression in terms of molarities for the aqueous reaction. 

Typically, the synthesis of AIPO4 involves the use of an aqueous reaction mixture containing an alumina source, a phosphate source, and an amine or/and a quaternary ammonium salt. The aluminum source is usually aluminum isopropoxide or pseudoboehmite, whereas orthophosphoric acid is most frequently the source of the phosphorus component. In the synthesis of SAPO, MeAPO, and MeAPSO materials, silica sol and/or a solution of the Me salt (usually acetate or sulfate) are introduced in the reactive mixture. Typical reaction mixtures have the molar compositions as follows (where R is an amine or/and a quaternary ammonium salt) ... 

The most current methods of obtaining pure HA are by hydrotermal and solid state reactions. However, when prepared from aqueous reactions either by precipitation or hydrolysis methods, the HA obtained is usually calcium deficient (Ca/P molar ratio lower than the stoichiometric value of 1.69). When the precipitation reaction is carried out under very basic conditions, the precipitate will contain carbonate, which will make the Ca/P molar ratio higher than the stoichiometric value. 

We can use the molarities and volumes of reactant solutions to predict the amount of product that will form in an aqueous reaction. 

Herein Pa and Pb are the micelle - water partition coefficients of A and B, respectively, defined as ratios of the concentrations in the micellar and aqueous phase [S] is the concentration of surfactant V. ai,s is fhe molar volume of the micellised surfactant and k and k , are the second-order rate constants for the reaction in the micellar pseudophase and in the aqueous phase, respectively. The appearance of the molar volume of the surfactant in this equation is somewhat alarming. It is difficult to identify the volume of the micellar pseudophase that can be regarded as the potential reaction volume. Moreover, the reactants are often not homogeneously distributed throughout the micelle and... 

Herein [5.2]i is the total number of moles of 5.2 present in the reaction mixture, divided by the total reaction volume V is the observed pseudo-first-order rate constant Vmrji,s is an estimate of the molar volume of micellised surfactant S 1 and k , are the second-order rate constants in the aqueous phase and in the micellar pseudophase, respectively (see Figure 5.2) V is the volume of the aqueous phase and Psj is the partition coefficient of 5.2 over the micellar pseudophase and water, expressed as a ratio of concentrations. From the dependence of [5.2]j/lq,fe on the concentration of surfactant, Pj... 

The high reactivity of the 5-position in 1.3-selenazoles toward electrophilic substitution was also observed on azocoupling. By reacting molar quantities of an aqueous solution of a diazonium salt with an ethanolic solution of a 2-arylamino selenazole. for example, the corresponding 2-arylamino-5 azoselenazoles are formed in a smooth reaction (100). They deposit from the deeply colored solution and form intenselv red-colored compounds after their recrystallization from a suitable solvent (Scheme 36l. 

Anhydrous gaseous or Hquid hydrogen sulfide is practically nonacidic, but aqueous solutions are weakly acid. The for the first hydrogen is 9.1 X 10 at 18°C for the second, is 1.2 x 10 . Reaction of hydrogen sulfide with one molar equivalent of sodium hydroxide gives sodium hydrosulfide with two molar equivalents of sodium hydroxide, sodium sulfide forms. Hydrogen sulfide reacts with sodium carbonate to produce sodium hydrosulfide... 

In a typical batch operation, carbon disulfide is added to four molar equivalents of 25—30 wt % aqueous ammonia in a stirred vessel, which is kept closed for the first one to two hours. The reaction is moderately exothermic and requires cooling. After two to three hours, when substantially all of the disulfide has reacted, the reaction mixture is heated to decompose dithiocarbamate and trithiocarbonate and vented to an absorption system to collect ammonia, hydrogen sulfide, and any unreacted carbon disulfide. 

The alkoxy titanate compounds formed by reaction of one mole of tetraalkyl titanate with one mole of a dialkanolamine are excellent esterification catalysts for the manufacture of phthalate-based plasticizers (112). If a 1 1 molar mixture of alkanolamine and water is used ia place of the alkanolamine, oligomeric titanate complexes are formed, which have high catalyst activity and can be used as thixotropic additives to paints and other aqueous coating formulations (113). 

Manufacturing Processing and Uses. In commercial production, aqueous urea solution is mixed with acetaldehyde in 1 1 molar ratios. An acid catalyst is introduced into the reaction mixture which is staged at various process temperatures. After neutralization with a base, the CDU is separated from the mother hquor by filtration or spray drying. 

It is useful to relate the molarity of the aqueous caustic soda (mi = S.O kmol NaOH/m ) to the other reactive species. Once the reactions shut, the composition of NaOH will decrease. However, it is possible to relate the molarity of the solution to the concentration of the reactive species at any reaction coordinate. Suppose that after a certain extent of reaction (8. IS) and (8.16) an analyzer is placed in the solution to measure the compositions of OH, HS and S with the measured... 

An ethereal solution approximately 2.5 molar in methyllithium is prepared from 17 ml of methyl iodide and 4 g of lithium metal in 200 ml of anhydrous ether. A mixture consisting of 150 ml anhydrous ether, 3 g (10 mmoles) of 3jS-hydroxy-5a-androstane-ll,17-dione and 60 ml (0.15 moles) of the above methyllithium solution are stirred at room temperature for 40 hr. The reaction mixture is diluted with 100 ml of water and the ether is removed by distillation. Filtration of the chilled aqueous phase yields 2.6 g (77%) of 1 la,17a-dimethyl-5a-androstane-3a,l l/ ,17j5-triol mp 149-154°. Recrystallization from acetone-hexane yields pure material mp 164-166° [a] —5° (CHCI3). 

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