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Water Chemistry
Published in Mary K. Theodore, Louis Theodore, Introduction to Environmental Management, 2021
Mary K. Theodore, Louis Theodore
The subject of chemical kinetics allows one to quantify how fast chemical reactions occur and answer why certain reactions are faster than others [11,12]. Chemical kinetics is often quantified through the measurement of the rates of change in concentrations of reactants and/or products. The most important factors that influence rates of chemical reactions are the nature and concentration of the reactant(s). Increasing the temperature of the system imparts more kinetic energy to molecules, thereby serving to increase rates of chemical reactions. The detailed explanation of how a reaction proceeds at a molecular level is called a reaction mechanism. Determination of reaction mechanisms requires a broad and detailed understanding of the properties of reactants and products, and the changes that occur before, during, and after a chemical reaction, and is often difficult if not impossible to confirm unequivocally [13].
Inorganic scale
Published in Jon Steinar Gudmundsson, Flow Assurance Solids in Oil and Gas Production, 2017
Concentration expresses the amount of substance in a solution. By substance is meant any form of atom, molecule and species. By species is meant any form of anion and cation in solution. Anions are negatively charged, for example the chloride Cl- $ \text{ Cl}^{-} $ ion. Cations are positively charged, for example the sodium ion Na+ $ \text{ Na}^{+} $ . Together they form common salt NaCl $ \text{ NaCl} $ without electrical charge. Common salt can be dissolved in a solution (brine in oil and gas production) and can exist as the solid crystal halite. In real solutions, the presence of dissolved atoms, molecules and species will influence whatever chemical interactions taking place. The concept of activity is used to express the effective concentration in liquid solutions. The concept of fugacity is used to express the effective partial pressures of gases in mixtures.
Fugacities, Activities, and Activity Coefficients in Liquid Mixtures of Nonelectrolytes
Published in Juan H. Vera, Grazyna Wilczek-Vera, Classical Thermodynamics of Fluid Systems, 2016
Juan H. Vera, Grazyna Wilczek-Vera
Molality, that is, the moles of solute per 1000 g of solvent, is a convenient way to express the concentration of dilute solutions. In this case, the fugacity of solute i at a molality mi is writen in Henry’s convention as f1=m˜γi,H(m)Hi,r(m)
Bioconvective magnetized oldroyd-B nanofluid flow in the presence of Joule heating with gyrotactic microorganisms
Published in Waves in Random and Complex Media, 2022
K. Gangadhar, K. Bhanu Lakshmi, T. Kannan, Ali J. Chamkha
The present study includes heat transport and mass transport, and the chemical reaction stimulation takes the prominent role as an outcome of extensive industrialized utilization analysis. The model of synthetic processing material, polymers, cooling towers, formation & diffusion of fog, temperature and fibrous inner coating, pollution, etc., are to be considered because of its vital role. Necessary materials are generated to go over the synthetic mechanical response to convert economy basic materials into cutting-edge items like oxidation and artificial parts, obliteration of harvests as consequences of cold, preparing food, humidity diffusion developed areas, etc. In a reactor, a chemical reaction is executed. Chemical reaction b/w the conventional fluid and nanoparticles are categorized as a similar reaction over a positive stage (or) heterogeneous reaction, i.e. enclosed by the boundary layer. The rate of a chemical reaction is associated with the concentration. Considering the relevant applications, various authors have considered and produced their consequences on chemical reaction results on the flow of mass heat transport with distinct geometries [34–51].
Magnetohydrodynamic nonlinear thermal radiative heat transfer of nanofluids over a flat plate in a porous medium in existence of variable thermal conductivity and chemical reaction
Published in International Journal of Ambient Energy, 2021
Impacts of chemical reaction in the boundary layer fluid flow cannot be underestimated. A chemical reaction in such situation occurs between a fluid and foreign mass. Chemical reaction can be ordered either through homogeneous or heterogeneous procedures. Reaction rate in first-order chemical reaction is directly proportional to the concentration. Kameswaran et al. (2012) studied hydromagnetic nanofluid flow over a stretching/shrinking surface with viscous dissipation and chemical reaction. MHD stagnation-point flow and heat transfer impinging on the stretched surface with chemical reaction are analysed by Mabood, Khan, and Ismail (2015). Srinivasacharya and Reddy (2016) addressed chemical reaction and radiation effects on mixed convection heat and mass transfer by a vertical plate in power-law fluid-saturated porous medium. Chemical reaction effect in MHD flow of elastico-viscous nanofluid is examined by Ramzan and Bilal (2016). Influence of chemical reaction in flow past an exponentially stretching surface is studied by Bhattacharyya (2012).
Modelling and analysis of haemoglobin catalytic reaction kinetic system
Published in Mathematical and Computer Modelling of Dynamical Systems, 2020
Yanhong Liu, Hui Lv, Bin Wang, Deyun Yang, Qiang Zhang
Practice has found that the probability of molecular encounters of various reactants in a certain space is proportional to the number of reactants [20]. When the concentration of reactants increases, the probability of molecular encounters increases; hence, the reaction rate increases. Thus, the reaction rate can be expressed as a function of the concentration of reactants. The following example describes the process of establishing a mathematical model of a chemical reaction. The reaction equation is the combination of moles of and moles of to produce product :