Reactants mole ratios

If a reaction is reversible, there is a maximum conversion that can be achieved, the equilibrium conversion, which is less than 1.0. Fixing the mole ratio of reactants, temperature, and pressure fixes the equilibrium conversion. ... 

A procedure for determining the stoichiometry between two reactants by preparing solutions containing different mole ratios of two reactants. 

This experiment describes the use of FIA for determining the stoichiometry of the Fe +-o-phenanthroline complex using the method of continuous variations and the mole-ratio method. Directions are also provided for determining the stoichiometry of the oxidation of ascorbic acid by dichromate and for determining the rate constant for the reaction at different pH levels and different concentration ratios of the reactants. 

This experiment examines the effect of reaction time, temperature, and mole ratio of reactants on the synthetic yield of acetylferrocene by a Eriedel-Crafts acylation of ferrocene. A central composite experimental design is used to find the optimum conditions, but the experiment could be modified to use a factorial design. 

Staged reactions, where only part of the initial reactants are added, either to consecutive reactors or with a time lag to the same reactor, maybe used to reduce dipentaerythritol content. This technique increases the effective formaldehyde-to-acetaldehyde mole ratio, maintaining the original stoichiometric one. It also permits easier thermal control of the reaction (66,67). Both batch and continuous reaction systems are used. The former have greater flexibiHty whereas the product of the latter has improved consistency (55,68). 

The nitro alcohols available in commercial quantities are manufactured by the condensation of nitroparaffins with formaldehyde [50-00-0]. These condensations are equiUbrium reactions, and potential exists for the formation of polymeric materials. Therefore, reaction conditions, eg, reaction time, temperature, mole ratio of the reactants, catalyst level, and catalyst removal, must be carefully controlled in order to obtain the desired nitro alcohol in good yield (6). Paraformaldehyde can be used in place of aqueous formaldehyde. A wide variety of basic catalysts, including amines, quaternary ammonium hydroxides, and inorganic hydroxides and carbonates, can be used. After completion of the reaction, the reaction mixture must be made acidic, either by addition of mineral acid or by removal of base by an ion-exchange resin in order to prevent reversal of the reaction during the isolation of the nitro alcohol (see Ion exchange). 

Precise coatrol of the course, speed, and extent of the reaction is essential for successful manufacture. Important factors are mole ratio of reactants catalyst (pH of reaction mixture) and reaction time and temperature. Amino resias are usually made by a batch process. The formaldehyde and other reactants are charged to a kettie, the pH adjusted, and the charge heated. Often the pH of the formaldehyde is adjusted before a dding the other reactants. Aqueous formaldehyde is most convenient to handle and lowest ia cost. 

Ammonium acetate and sodium methoxide are effective catalysts for the ammonolysis of soybean oil (49). Polyfunctional amines and amino alcohols such as ethylenediamine, ethanolamine, and diethanolamine react to give useful intermediates. Ethylenediamine can form either a monoamide or a diamide depending on the mole ratio of reactants. With an equimolar ratio of reactants and a temperature of >250° C, a cyclization reaction occurs to give imidazolines with ethylenediamine (48) ... 

In a study of the kinetics of the reaction of 1-butanol with acetic acid at 0—120°C, an empirical equation was developed that permits estimation of the value of the rate constant with a deviation of 15.3% from the molar ratio of reactants, catalyst concentration, and temperature (30). This study was conducted usiag sulfuric acid as catalyst with a mole ratio of 1-butanol to acetic acid of 3 19.6, and a catalyst concentration of 0—0.14 wt %. 

Product distrihution among the chloromethanes depends primarily on the mole ratio of the reactants. For example, the yield of mono-chloromethane could he increased to 80% hy increasing the CH4/CI2 mole ratio to 10 1 at 450°C. If dichloromethane is desired, the CH4/CI2 ratio is lowered and the monochloromethane recycled. Decreasing the CH4/CI2 ratio generally increases poly substitution and the chloroform and carhon tetrachloride yield. 

The relative ratios of the ethanolamines produced depend principally on the ethylene oxide/ammonia ratio. A low EO/NH3 ratio increases monoethanolamine yield. Increasing this ratio increases the yield of di-and triethanolamines. Table 7-1 shows the weight ratios of ethanolamines as a function of the mole ratios of the reactants. ... 

Weight ratios of ethanolamines as a function of the mole ratios of the reactants ... 

Good results may sometimes be achieved with a 4 1 or 5 1 mole ratio of trichlorosilane to carboxylic acid. Excess trichlorosilane is desirable to compensate for losses of this volatile reactant over extended reflux periods. 

To find out the mass of a product that can be formed from a known mass of a reactant, we first convert the grams of reactant into moles, use the mole ratio from the balanced equation, and then convert the moles of product formed into grams. Essentially, we go through three steps ... 

In this approach, we use the mole ratio from the chemical equation to determine whether there is enough of one reactant to react with another. 

STRATEGY We convert from the given volume of gas into moles of molecules (by using the molar volume), then into moles of reactant molecules or formula units (by using a mole ratio), and then into the mass of reactant (by using its molar mass). If the molar volume at the stated conditions is not available, then use the ideal gas law to calculate the amount of gas molecules. 

Vj is the stoichiometric coefficient for species i in the reaction. By convention, the value of v is positive for the products and negative for the reactants. The stoichiometric coefficients relate the simplest ratio of the number of moles of reactant and product species, involved in the reaction. 

Number of Mole Ratios per Number of Reactants and Products... 

This graph shows the number of mole ratios that can be determined given the number of reactants and products of a chemical reaction. If this trend continues, how many mole ratios can be formed with a chemical reaction that has a sum of eight reactants and products ... 

When two substances react, they react in exact amounts. You can determine what amounts of the two reactants are needed to react completely with each other by means of mole ratios based on the balanced chemical equation for the reaction. In the laboratory, precise amounts of the reactants are rarely used in a reaction. Usually, there is an excess of one of the reactants. As soon as the other reactant is used up, the reaction stops. The reactant that is used up is called the limiting reactant. Based on the quantities of each reactant and the balanced chemical equation, you can predict which substance in a reaction is the limiting reactant. 

SYil MisSIS The polymerization can be run in any one of several solvents, including dimethylsulfoxide, 1,4-dioxacyclohexane, dimethylformamide, and dimethylacetamide. Dimethylsulfoxide or mixtures based on dimethylsulfoxide have been used as the solvent for all reactions reported here. In other solvents, the product often precipitates as the reaction proceeds. This reaction can be successfully run with mole ratios of the reactants in the following ranges 1. hydroperoxide to calcium chloride 0.25 to 32> and 2. hydroperoxide to lignin (M ) 21 to 115 ... 

Ans. That would imply a certain mole ratio to the other reactants and products, which is not correct. 

The balanced chemical equation may also be used to express the ratios of moles of reactants and products involved. Thus, for the reaction whose equation is given above, 1 mol of N, reacts with 3 mol of H 2 to produce 2 mol of NH,. It is also true that 4 mol of nitrogen can react with 12 mol of hydrogen to produce 8 mol of ammonia, and so on. 

Since the reactants react in a 1 1 mole ratio, the Br2 is in limiting quantity ... 

The product distribution is insensitive to the concentration of reactant B. If B is cheap and does not offer a potential pollution problem downstream, its concentration may be kept at any convenient level. If B is costly or must be removed for other reasons, one has the options of operating with low B concentrations at high conversions in a relatively large reactor to produce a product containing very little B, or of operating at higher B concentrations in a smaller reactor with separation and recycle of unused B. The specified product distribution requires that the mole ratio of V to W be 3 1. To produce 1 mole of W and three of F, one must consume 4 moles of A and 5 moles of B. The feed ratio employed in an actual situation may differ appreciably from 1.25 to enhance the reaction rate or to allow for discarding some A and B. 

B The assumptions include no heat loss to the surroundings or to the calorimeter, a solution density of 1.00 g/mL, a specific heat of 4.18 J g 1 °C 1, and that the initial and final solution volumes are the same. The equation for the reaction that occurs is NaOH(aq) + HCl(aq) - NaCl(aq) + H20(l). Since the two reactants combine in a one to one mole ratio, the limiting reactant is the one present in smaller amount. 

Ethyl formate is to be produced from ethanol and formic acid in a continuous flow tubular reactor operated at a constant temperature of 303 K (30°C). The reactants will be fed to the reactor in the proportions 1 mole HCOOH 5 moles C2H5OH at a combined flowrate of 0.0002 m3/s (0.72 m3/h). The reaction will be catalysed by a small amount of sulphuric acid. At the temperature, mole ratio, and catalyst concentration to be used, the rate equation determined from small-scale batch experiments has been found to be ... 

The amount of heat evolved should be proportional to the mole ratios of the reactants involved. If varying volumes of reactants were allowed, calculations would need to be performed for each mixture so that a valid comparison could be made. 

Positive Slope The mL and mole ratio for equivalency is 4 NaClO to 1 Na2S203 (see 1 above). In examining the data table, it can be seen that the Na2S203 is in excess, with the NaClO being the limiting reactant for example, in Trial 7, for 30 mL of 0.500 M NaClO,... 

These are produced by the polycondensation of a phenol or a mixture of phenol with formaldehyde. This condensation reaction is catalysed by acids or alkalies. The nature of the product formed by this condensation reactions depends upon the type of catalyst and the mole ratio of the reactants. 

The moles of reactant per coefficient of that reactant in the balanced chemical equation is calculated. The reactant that has the smallest mole-to-coefficient ratio is the limiting reactant. This is the method that many use. 

Convert the masses of the reactants and products to moles using their molar masses. Using the mole ratios from the balanced chemical equation, it is possible to determine how much material should react or be produced. These calculated values can be compared to the observed values. 

---