Temperature-moles product

Amine-terminated, G3 (PAMAM) dendrimer, (0.316 g 45.7 moles) was dissolved in anhydrous methyl sulfoxide (5 ml) in a 100 ml round-bottom flask flushed with dry nitrogen. After dendrimer had completely dissolved, succinic anhydride (Aldrich) (0.363 g 3.6 mmol) was added to the reaction mixture with vigorous stirring, and the mixture was allowed to react for 24 h at room temperature. The product solution was diluted with deionized water, transferred to 3500 MWCO dialysis tubing (Spectrum) and dialyzed against deionized water (18 Mil) for 3 d. The retentate solution was clarified by filtration through Whatman No. 1 filter paper, concentrated with a rotary evaporator, and lyophilized to yield a colorless powder (0.435 g, 94%). The product was analyzed by 13C-NMR, FT-IR, SEC and MALDI-MS. The analytical data were consistent with the expected carboxylic acid-terminated product. 

Adiabatic flame temperatures and product mole fractions obtained from the reaction of hydrogen and oxygen in different mixture ratios are shown in Table 2.2. The maximum adiabatic flame temperature is obtained from the mixture of 2H2 -1- O2, which is the stoichiometric ratio for the reaction. 

B. Ethyl pyrrole-2-carboxylate. In a 1-1. three-necked round-bottomed flask equipped with a sealed mechanical stirrer and powder funnel are place 1.0 g. of sodium and 300 ml. of anhydrous ethanol. When the sodium is dissolved, 75 g. (0.35 mole) of pyrrol-2-yl trichloromethyl ketone from Part A is added portionwise over a 10-minute period (Note 4). After the addition is complete, the solution is stirred 30 minutes, then concentrated to dryness using a rotary evaporator. The oily residue is partitioned between 200 ml. of ether and 25 ml. of 3 N hydrochloric acid. The ether layer is separated, and the aqueous layer is washed once with 100 ml. of ether. The ether solutions are combined, washed once with 25 ml. of saturated sodium bicarbonate solution, dried with magnesium sulfate, and concentrated by distillation. The residue is fractionated at reduced pressure to give 44.0-44.5 g. (91-92%) of ethyl pyrrole-2 carboxylate as a pale yellow oil, b.p. 125-128° (25 mm.) (Note 5). The yield based on pyrrole is 70-74%. Upon standing at room temperature the product crystallizes, m.p. 40-42°. 

In a hood, through a rapidly stirred suspension of 76 gm (0.396 mole) of cyclohexanoneazine in 300 ml of petroleum ether (b.p. 60°-90°C) cooled to —60°C is passed a slow stream of gaseous chlorine until a slight excess of the gas is noted. The excess of chlorine is removed by ventilation at the water aspirator. Then the solution is concentrated to half-volume by gentle evaporation at reduced pressure. The reaction system is filtered free from tarry impurities and the filtrate is allowed to stand for 24 hr at room temperature. The product gradually separates out and is isolated by filtration. Evaporation of the mother liquor may afford another crop of product. The total yield is 81.5 gm (78 %). The product, after recrystallization from petroleum ether, has a melting point of 66°C. (NOTE Since aliphatic azo compounds are inherently unstable and may serve as free radical sources, the stability of the product should always be checked with due precautions, and excessive exposure to heat should always be avoided.)... 

The reaction efficiency depends on temperature, mole ratio of reagents, and intensity of the visible light. These parameters were easily managed. Moreover, the atomic utihzation of bromine is greatly increased. In this method, l IBr and water are the reagent and by-product respectively, providing a process that is eco-friendly and cost effective (48% aqueous HBr is inexpensive). 

Commercially available CsF (760 mg, 5 mmol) was added to 2 or 10% mole (relative to CsF) of the tetraalkylammonium salt (Bu4NBr or Aliquat 336). The mixture was stirred for 5 min with a mechanical stirrer. The liquid substrate (2.5 mmol) were then added, the mixture was stirred for 5 min more and left stirring for the indicated period at the appropriate temperature. Organic products were obtained by a simple filtration on Florisil (on which ammonium salts remain absorbed) after addition of Et20 (50 mL). The solvent was evaporated and the product identified by spectroscopic methods. 

Since product distributions depend on the relative rates of competing reactions, effects of temperature on products depend on differences in activation energies, AE. For each pair of competing reactions of the tert-Bu02 radicals, the following AE values (in kilocalories per mole) and qualitative effects of increasing temperature are estimated. Some of these values were considered under Liquid-Phase Oxidations. ... 

Neat isopropyl methylphosphinate (1) reacts exothermically on dropwise addition to methyl triflate to form a phosphonium salt (2), NMR 6 +73.4 (downfield from external H,P0.) J = 656 Hz, which yields isopropyl methyl methylphosphonite (3), when slowly added to a cold benzene solution containing excess tri-ethylamine (TEA). On warming to room temperature, the product was obtained as a benzene/TEA solution, which separated from a heavier liquid layer that consisted mainly of amine salt byproducts in benzene/TEA. When (R)-(+)-l (25% enantiomorphic excess) was used, a solution of (R)-(+)-3 (5 +176.6) was obtained in 60% yield, 90 mole-% pure with respect to its organophosphorus content. 2(Pie specific rotation of this product was calculated to be [a]D + 67.7 (c 2.6, benzene), if optically pure (+)-l starting material... 

A fresh solution of 1 mole-equivalent of p-fluorobenzylamine and 1 mole equivalent methylamine is added to a solution of 1 mole-equivalent 7-oxo-8-methylnonanoic acid in 20 ml ethanol. The mixture is warmed at 40°C for a night. 0.1 g of platinum oxide is then added and the mixture is hydrogenated under ordinary pressure at 40°C. After the theoretical amount of hydrogen has been absorbed, the catalyst is filtered off and the solvent is evaporated under reduced pressure. The oily residue crystallized quickly, at room temperature. The product is purified by recrystallizing it from ethyl acetate and is dried over phosphoric anhydride in a closed vessel. (+/-)-7-((p-Fluorobenzyl)amino)-8-methylnonanoic acid is a crystalline solid MP 88°-89°C. 

At room temperature the product kT is about 400, in terms of sq. A. per molecule. A perfect gaseous film would thus exert a pressure of 1 dyne at 400 sq. A. It will be seen later that the molecules in gaseous films nearly always lie flat, and since the area occupied by an aliphatic substance containing some sixteen carbon atoms in the chain will be of the order 120 sq. A., the instruments used for investigating the gaseous state of the films must be capable of measuring pressures down to a very small fraction of a dyne, in order that the films may be so dilute that the mole-... 

Tetrahydrofuran (THF) (80 mL, freshly distilled from sodium benzophenone ketyl) is added from a 250-mL Schienk flask to bis(acetonitrile)tetrachloro-molybdenum(IV) (20 g, 0.052 mole) in a 250-mL Schienk flask and the mixture is stirred rapidly for 2 hours to give a yellow suspension of tetrachlorobis-(tetrahydrofuran)molybdenum(IV). The complex is filtered through a Schienk filter, washed with THF (20 mL), and dried in vacuo (10 2 torr) at room temperature. The product is obtained as a microcrystalline orange-yellow powder in yields of 15-17 g, 63-71%. The product is not analytically pure. Anal. Calcd. for CbH1602C14Mo C, 25.1 H, 4.9. Found C, 26.5 H, 4.2. However, it is sufficiently pure for subsequent reactions. 

Anhydrous nickel(II) chloride (1.30 g., 0.01 mole) is dissolved in 100 ml. of absolute ethanol in a 200-ml. round-bottomed flask fitted with a reflux condenser and nitrogen inlet and outlet. Diethyl phenylphosphonite (10 g., 0.05 mole) is added, and the solution is heated to reflux. After 3 hours, the heat is removed and the solution is allowed to cool slowly to room temperature. The product separates as yellow crystals from the solution. With a stream of nitrogen passing through the flask, the mother liquor is transferred by syringe to another 200-ml. flask the crystals are washed with two 20-ml. portions of absolute ethanol, and dried in vacuo. Concentration of the mother liquor to 30 ml. yields additional product. Yield is 8.2 g. (97%). Anal. Calcd. for C HeoOsNiP C, 56.51 H, 7.11 P, 14.60. Found C, 56.27 H, 7.17 P, 14.54. 

Diamantanedicarboxylic acid and excess thionyl chloride were refluxed until a clear solution was obtained and then concentrated. The crude 4,9-diamantanedi-carboxylic acid chloride (0.0211 mole) was slowly added to a chilled solution of AICI3 (6.75 g) and anisole (22.8 g), and the mixture was stirred overnight at ambient temperature. The product was precipitated by pouring into O.IM aqueous HCl, then stirred, filtered, and the solid further stirred in methanol to remove unreacted anisole. The white solid was re-crystallized from a mixture of 700 ml toluene and 100 ml THF and the product was isolated in 72% yield, MP = 213-214°C. 

A flowchart for a program to implement this procedure is shown in Figure P8.1. Write the program and test it by estimating the flash lank temperature and product stream flow rates (mol/s) and compositions (mole fractions) for the flash vaporization of one mol/s of an equimolar mixture of n-pentane (A) and n-hexane (B), if the feed temperature is llOX and the tank pressure is 1.0 atm. 

Dry hydrogen chloride is passed into 50 g. (0.48 mole) of styrene cooled to —80° until the gain in weight of the reaction mixture is 28 g. Freshly distilled styrene (b.p. 40°/12-13 mm.) is used. After it has been warmed slowly to room temperature, the product is distilled and gives 48.5 g. (68%) of a-chloroethylbenzene, b.p. 73°/ll mm. 

Prepare a Fortran program that will use the input number of atoms of C, H, and O in the fuel, the reactant moles and temperatures, and product composition and temperature, to make both material and energy balances for a combustion process. Assume that the process is adiabatic. Take the heat capacity equations and AH/ data from Appendix K and Table D.l. 

From the principles of thermodynamics and certain thermodynamic data the maximum extent to which a chemical reaction can proceed may be calculated. For example, at 1 atm pressure and a temperature of 680°C, starting with 1 mole of sulfur dioxide and mole of oxygen, 50% of the sulfur dioxide can be converted to sulfur trioxide. Such thermodynamic calculations result in maximum values for the conversion of a chemical reaction, since they are correct only for equilibrium conditions, conditions such that there is no further tendency for change with respect to time. It follows that the net rate of a chemical reaction must be zero at this equilibrium point. Thus a plot of reaction rate [for example, in units of g moles product/(sec) (unit volume reaction mixture)] vs time would always approach zero as the time approached infinity. Such a situation is depicted in curve A of Fig. 1-1, where the rate approaches zero asymptotically. Of course, for some cases equilibrium may be reached more rapidly, so that the rate becomes almost zero at a finite time, as illustrated by curve B. 

From the kinetic theory of gases, without a knowledge of the law of distribution of velocities (i.e. of the way in which the number depends on v), we have found that the product of pressure and volume is a function only of the mean kinetic energy of the gas. But we have also an empirical law, the law of Boyle (1660) and Mariotte (1676), viz. at constant temperature the product of the pressure and volume of an ideal gas is constant. We must conclude from this that U, the mean kinetic energy per mole, depends only on the temperature of the gas. 

Conditions that affect the robustness of the SOE PCR include annealing temperature, mole ratio of pre-SOE products, and competing undesired amplification. If the SOE product is in low abundance or appears contaminated by unwanted product, try a gradient of annealing temperatures in the SOE PCR program to optimize that parameter. Also, adjusting the ratio of pre-SOE product 1 to pre-SOE product 2 in the SOE reaction mixture may yield improved... 

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