Reaction stoichiometry gases

What Do We Need to Know Already The concepts of chemical equilibrium are related to those of physical equilibrium (Sections 8.1-8.3). Because chemical equilibrium depends on the thermodynamics of chemical reactions, we need to know about the Gibbs free energy of reaction (Section 7.13) and standard enthalpies of formation (Section 6.18). Ghemical equilibrium calculations require a thorough knowledge of molar concentration (Section G), reaction stoichiometry (Section L), and the gas laws (Ghapter 4). 

A tubular reactor is considered in which the gas-phase reaction leads to a change in the molar flow rate and thus in the linear gas velocity. The reaction stoichiometry is represented by... 

When heated above 200 °C, pure 5-methyl-2-oxazolidinone decomposes into two products, C02 gas and N-(2-hydroxypropyl) imidaz-olidinone. The reaction stoichiometry is ... 

Equation A may now be used to determine the diffusivity of sulfur dioxide in the gas mixture. The flux ratios may be determined from the reaction stoichiometry. 

We can use the gas law relationships, especially the ideal gas law and the combined gas law, in reaction stoichiometry problems. For example, suppose you have 2.50 g of an impure sample of KC103 and you want to determine how many grams of pure KC103 are present. You heat the mixture and the KC103 decomposes according to the equation ... 

In this chapter, you learned about the properties of gases. You learned that you can use the combined gas law, the ideal gas law, or the individual gas laws to calculate certain gas quantities, such as temperature and pressure. You also learned that these equations could also be useful in reaction stoichiometry problems involving gases. You learned the postulates of the Kinetic-Molecular... 

The gas law relationships can be used in reaction stoichiometry problems. For example, suppose you have a mixture of KC103 and NaCl, and you want to determine how many... 

Gas stoichiometry—Know how to apply the gas laws to reaction stoichiometry problems. 

To follow the same analysis as in two-phase systems, the stoichiometry of the reaction should be used for the determination of the final moles in the gas phase after the reaction. However, in sluny reactors, a liquid phase is involved and the reactants are dissolved and react in the liquid phase. In this case, the moles remaining in the gas phase after the reaction are not only determined from the reaction stoichiometry. This is why a part of the moles that disappear from the gas phase is unreacted and dissolved in the liquid. This situation introduces some complications in the determination of the expansion factor. 

Usually the effect of chemical reactions in RA processes is advantageous only in the region of low gas-phase concentrations, due to limitations stemming from the reaction stoichiometry or equilibrium (20). Further difficulties of RA applications may be caused by the reaction heat through exothermic reactions and by relatively difficult solvent regeneration (21,22). Most RA processes are... 

In reaction stoichiometry problems involving gases, the ideal gas law provides a means to compute moles from pressure or volume data. 

Pressure measurement devices such as a manometer are used without disturbing the system being monitored. Another type of reacting system that can be monitored involves one of the products being quantitatively removed by a solid or liquid reagent that does not affect the reaction. An example is the removal of an acid formed by reactions in the gas phase using hydroxide solutions. From the reaction stoichiometry and measurements of the total pressure as a function of time, it is possible to determine the extent of the reaction and the partial pressure or concentrations of the reactant and product species at the time of measurement. 

The reaction stoichiometry may be determined from the amount of anchored metal and the number of ligands in the coordination sphere, or the amount of gas evolved (e.g. HC1 or C2H4) during hydrolysis/dc-composition, provided that it docs not adsorb on the support. 

Sulphur is detrimental to the sjmthesis and trace amounts of sulphur are removed using zine oxide prior to synthesis. After the production of synthesis gas, the methanol sjmthesis requires compression to about lOObar. The methanol synthesis loop con rises a reactor, a separator and recompression of the reeyele gas. A purge gas can be used to produce power supplemented by steam raised in the methanol reactor and the coal gasifier. The crude methanol produced can be upgraded to chemical grade product by distillation. The intermediate methanol is passed into storage. The reaction stoichiometry is ... 

To complete the picture, the flux of gas. A, must be related to the change in B and the size shrinking core radius, r. This can be accomplished by considering that the change in moles of is equal to b times the change in the moles of A, from the reaction stoichiometry, which is also equal to the flux J described by equations (5.27), (5.28), (5.31), and (5.32) ... 

The early chapters in this book deal with chemical reactions. Stoichiometry is covered in Chapters 3 and 4, with special emphasis on reactions in aqueous solutions. The properties of gases are treated in Chapter 5, followed by coverage of gas phase equilibria in Chapter 6. Acid-base equilibria are covered in Chapter 7, and Chapter 8 deals with additional aqueous equilibria. Thermodynamics is covered in two chapters Chapter 9 deals with thermochemistry and the first law of thermodynamics Chapter 10 treats the topics associated with the second law of thermodynamics. The discussion of electrochemistry follows in Chapter 11. Atomic theory and quantum mechanics are covered in Chapter 12, followed by two chapters on chemical bonding and modern spectroscopy (Chapters 13 and 14). Chemical kinetics is discussed in Chapter 15, followed by coverage of solids and liquids in Chapter 16, and the physical properties of solutions in Chapter 17. A systematic treatment of the descriptive chemistry of the representative elements is given in Chapters 18 and 19, and of the transition metals in Chapter 20. Chapter 21 covers topics in nuclear chemistry and Chapter 22 provides an introduction to organic chemistry and to the most important biomolecules. 

The lower CO2 selectivity observed on small pellets (Table V) apparently reflects the transport-limited removal of water, a product of the FT synthesis. CO2 selectivity also increases with increasing site density, CO conversion, and water concentration in the catalyst bed this suggests that CO2 forms in secondary water-gas shift reactions that become significant as intrapellet water fugacities rise because of transport restrictions. Transport rates of CO and H2O in hydrocarbon liquids are qualitatively similar and the reaction stoichiometry requires that one water molecule must be removed... 

Stoichiometry (gas-phase reaction with no pressure drop) ... 

The SCR process consists of the reduction of NO (typically 95% NO and 5% NO2 v/v) with NH3. The reaction stoichiometry is usually represented as 4NO + 4NH3 + 02 4N2 + 6H2O. This reaction is selectively effected by the catalyst, since the direct oxidation of ammonia by oxygen is prevented In the case of the treatment of sulfur-containing gas streams, the DcNO reaction is accompanied by the catalytic oxidation of SO2 to SO3 Oxidation of SO2 is highly undesirable because SO3 is known to react with water and residual ammonia to form ammonium sulfates, which can damage the process equipment. 

To include a safety margin, the operating gas velocity will be chosen to exceed 1.2 Utr. As the minimum gas flow in the riser is determined by the reaction stoichiometry, the gas velocity and the riser diameter cannot be chosen independently. 

Apply your knowledge of reaction stoichiometry to solve gas stoichiometry problems. 

The molar mass of glueose is 180.15 g mol". From this, we ean ealculate the number of moles of glucose formed and, using the reaction stoichiometry, determine the number of moles of CO2 needed. With that information and the other information provided in the problem, we ean use the ideal gas law to ealculate the volume of air that is needed ... 

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