Products calculating amounts

Depending on the desired levels of diphenylsiloxane units and the molecular weight of the final product, calculated amounts of D, D and 1,3-bis(y-aminopropyl)tetramethyldisiloxane were introduced into a round bottom, 3-necked flask fitted with a condenser, thermometer and argon inlet. Later 0.01-0.1% by weight of finely ground... 

A solution of 50 g of 1 -azabicyclo [2.2.2] -3-octanone hydrochloride in 200 cc of water was hydrogenated at room temperature and 50 atm pressure with 1 g of platinum oxide as catalyst. After the calculated amount of hydrogen had been absorbed, the mixture was filtered and concentrated in vacuo to dryness. The residual product was recrystallized from a mixture of methanol and acetone and formed prisms melting above 300°C. It was identified as 1 -ezabicy-clo[2.2.2] -3-octanol hydrochloride. 

A mixture of 9.6 parts of 4-amino-3-nitrobenzophenone, 160 parts of methanol, 8 parts of concentrated hydrochloric acid and 1 part of palladium-on-charcoal catalyst 10% is hydrogenated at normal pressure and at room temperature. After the calculated amount of hydrogen is taken up, hydrogenation is stopped. The catalyst is filtered off and the solvent is evaporated. The solid residue is triturated in 2-propanol. The latter is partly evaporated and the solid product is filtered off, washed with 2-propanol and dried, yielding 3,4-diaminobenzophenone hydrochloride MP 207 C. 

The product is hydrogenated in 4,000 cc of ethanol at room temperature and under normal atmospheric pressure with a catalyst prepared In the usual manner from 400 g of Raney nickel alloy. The calculated amount of hydrogen is taken up in approximately 75 hours. After filtration and evaporation to a small volume, the residue Is distributed between 1,000 cc of chloroform and water each. The chloroform solution is then dried over sodium sulfate and evaporated to a small volume. Precipitation of the hydrogenation product with petroleum ether yields an amorphous white powder which Is filtered by suction, washed with petroleum ether and dried at 50°C In a high vacuum. 1. athyl-2-podophyllinic acid hydrazide is obtained in a practically quantitative yield. 

Remember that in deciding on the theoretical yield of product, you choose the smaller of the two calculated amounts. To see why this must be the case, refer back to Example 3.10b. There 1.20 g of Sb was mixed with 2.40 g of I2. Calculations show that the theoretical yield of Sbl3 is 3.17 g, and 0.43 g of Sb is left over. Thus... 

Cyclohexylcarbinol (6, 22), In the preparation of cyclohexylcarbinol as described in Vol. 6, 22, a high-boiling by-product, the cyclohexylcarbinol acetal of formaldehyde, is sometimes obtained. The by-product becomes the main product if the steam distillation of the reaction mixture is omitted. The by-product can usually be avoided if twice the calculated amount to decompose the Grignard reagent of io per cent sulfuric acid is added to the reaction mixture before steam distillation is earned out. The acetal which may be present is thus hydrolyzed. 

A suspension of the ketone 28 (5.9 g, 20.5 mmol) in xylene (150mL) was refluxed in an apparatus fitted with a water separator until the calculated amount of HzO had been collected. The product separated on cooling yield 2.5 g (45%) mp 160-162 X (xylene). 

The theoretical yield of a reaction is the maximum quantity (amount, mass, or volume) of product that can be obtained from a given quantity of reactant. The quantities of products calculated from a given mass of reactant in Section L were all theoretical yields. The percentage yield is the fraction of the theoretical yield actually produced, expressed as a percentage ... 

That is, the reaction of primary alcohols or ethers with a calculated amount of BTMA Br3 in carbon tetrachloride-water in the presence of Na2HP04 at 60°C gave dimeric esters in good yields. In the case of benzyl alcohol, the only oxidation product was benzaldehyde (Fig. 20). 

The reaction at Eq. (12) allows the preparation of Na2S4 and K2S5 from the alkali metals, hydrogen sulfide and sulfur in anhydrous ethanol (ROH). First the metal is dissolved in the alcohol with formation of ethanolate (MOR) and hydrogen. Bubbling of H2S into this solution produces the hydrogen sulfide (MHS). To obtain the polysulfide the solution is refluxed with the calculated amount of elemental sulfur. After partial evaporation of the solvent and subsequent cooling the product precipitates. 

To illustrate this latter point, Figure 5 shows the calculated amount of coal required for hydrogen manufacture as a function of the rank of the starting coal and the composition of the desired products (10). In these calculations a 12.5% methane byproduct was assumed and the thermal efficiency of the hydrogen generation was assumed to be 70%. 

Upon adding the calculated amount of water to ethyl oxomalonate, decolorization takes place immediately with evolution of heat, and on cooling a solid mass of ethyl dihydroxy-malonate results. After recrystallization from chloroform the product melts at 56-57°. (Communicated by Elizabeth Gilman and T. B. Johnson.)... 

In the problem above, the amount of product calculated based upon the limiting reactant concept is the maximum amount of product that will form from the specified amounts of reactants. This maximum amount of product is the theoretical yield. However, rarely is the amount that is actually formed (the actual yield) the same as the theoretical yield. Normally it is less. There are many reasons for this, but the principal one is that most reactions do not go to completion they establish an equilibrium system (see Chapter 14 for a discussion on chemical equilibrium). For whatever reason, not as much product as expected is formed. We can judge the efficiency of the reaction by calculating the percent yield. The percent yield (% yield) is the actual yield divided by the theoretical yield and the resultant multiplied by 100 in order to generate a percentage ... 

As far as the velocity and the extent of the conversion are concerned, the two processes are, however, altogether different. Whereas an acid is practically instantaneously and completely converted into a salt by an equivalent amount of a sufficiently strong base (neutralisation), a process on which, indeed, alkalimetry and acidimetry depend, it is not possible to obtain from equimolecular amounts of acid and alcohol the theoretical (calculated) amount of ester. A certain maximal quantity of ester is formed, but always falls short of the theoretical, and it is impossible, even by indefinitely extending the duration of the reaction, to make the unchanged acid and alcohol produce ester in excess of that maximum. If, for example, equimolecular amounts of acetic acid and alcohol are allowed to interact in a closed system, only two-thirds of each enter into reaction, and it is impossible to induce the remaining third of acetic acid to react with that of alcohol. The maximum yield of ester therefore amounts to only two-thirds, or 66-7 per cent, of the theoretical quantity. The quantitative difference in the course of the two reactions mentioned above depends on the fact that esterification is a so-called reversible reaction , i.e. one in which the reaction products represented on the right-hand side of the equation (ester and water) also interact in the opposite direction ... 

The program repeats the entire calculation through statement 140 for each column in turn and then proceeds to the next section in which the calculated amounts of each component in all products leaving the system of columns are summed in prdsum. Each side flow or flow from an end stage is examined to determine whether it goes to some other point in the column systems if not, it is a product. The over-all unbalance for each component is calculated as cunbal, equal to the total input of the component to the column system minus the total output. 

The recovery factor is defined as the ratio of additional steam provided by injection to the amount of water injected over the same period of time. Additional steam is the steam produced at the new decline rate (or improvement rate) due to injection minus the steam production calculated at a decline rate without re-injection. The recovery factor defined on the basis of production data may be different from that defined on the basis of geochemical data if considered on a well-by-well basis. However, the combined recovery from all production wells affected by one or more injection wells should agree when applying both methods given sufficient time, since (1) the total amount of boil water should appear as steam in production wells and be reflected in the production data, and (2) the steam originally to be produced from a given well but replaced by injection-derived steam should eventually be produced in other wells. 

Fio. 2. Calculated amounts of primary reaction products formed relative to total products in coball-catalyzed CO hydrogenation. (Reprinted from Ref. 38, by courtesy of Marcel Dekker, Inc.) Reaction is the same as that of Fig. I. 

Preparation from Borax. Dissolve 12 g of borax in 25 ml of water in a beaker with heating. What is the reaction of the solution to litmus and what is it due to Write the molecular and net-ionic equations of the borax hydrolysis reaction. How can the hydrolysis of borax be facilitated Calculate what amount of a 25% hydrochloric acid solution is needed to prepare boric acid from 12 g of borax. Measure off the calculated amount of acid, and taking a small excess amount, pour the acid into the hot borax solution. Let the solution cool slowly. What substance crystallizes Filter off the crystals on a Buchner funnel, dry them between filter paper sheets, and recrystallize them from hot water, guiding yourself by the table of solubilities. Determine the product yield (in per cent). Keep the prepared boric acid for the following experiments. 

Preparation of Lead(Il) Acetate (Lead Sugar). Dissolve 3 g of lead(II) oxide in a calculated amount of a hot 50% acetic acid solution. Filter the solution, and add 1 ml of acetic acid with the same concentration to the filtrate. Evaporate the latter up to half of its initial volume and let it stand for crystallization. Separate the crystals from the mother liquor on a Buchner funnel and wash them with small portions of ethanol, and then with ether (for what purpose ), What is the composition of the product ... 

The calculated amount of boron trifluoride-dicthyl ether complex was added to a solution of hex-1-ene (3.2 mmol) in dichloromethanc (10mL) followed by a 1 M solution of methyl hypochlorite (1.6mL, (1.6 mmol). b Since 14 and 15 + 16 are formed in nearly equal amounts, the quantity of BF, is nearly sufficient to form products in the same ratio as in the other runs. c Unreacted methyl hypochlorite remained after several hours. 

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