Introduction
An informal definition of Henry’s Law states that the solubility of a compound in a solvent is directly proportional to the partial pressure of the compound in the vapour phase, at low partial pressures. In a plot of concentration dissolved vs. partial pressure, the slope of the curve is the Henry’s Law Constant (HLC). The system is taken to be at equilibrium; that is the Gibbs free energy is at a global minimum so the macroscopic properties of the system are static. Unfortunately this definition is often too simplistic to be used in most practical applications for reasons which will be explained later.
The formal definition of the HLC is:
lim┬(x_i→0)〖(f ̂_i^L)/x_i 〗=H_ij (1)
where f ̂_i^L is the liquid fugacity of the solute i, xi is the mole fraction, and Hij is the HLC of the solute, in the solvent j. It is important to mention that the HLC is specific a particular solute-solvent pair. A common mistake is to use the vapour-phase fugacity instead of the liquid-phase one, and simply to take the HLC as the ratio of the vapour-phase fugacity to liquid phase composition. This is incorrect as it assumes that the activity coefficients are equal to one, and the HLC is the reference fugacity (Carroll, 1991). The most common form of Henry’s Law used assumes that the vapour is at a pressure low enough such that it acts as an ideal gas. When this assumption is made both the activity coefficient, γ, and the fugacity coefficient, φ ̂, are equal to unity.
x_i H_ij=y_i P (2)
This form of Henry’s Law can be used up to a pressure of about 200 kPa and liquid concentrations of 1 mol% (Carroll, 1991). This shows that at low partial pressures a plot of mole fraction of a compound vs. partial pressure of the compound in the g...
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In terms of kinetics, specifically speaking, the rate of reaction as determined by the concentration, reaction orders, and rate constant with each species in a chemical reaction. By using the concentration of the catalyst and the temperature, the overall reaction rate was determined. The rate constants of K0, Kobs, and Kcat can be derived via the plotting of the absorption at 400nm of p-nitrophenol vs. the concentration of the catalyst imidazole. Lastly, the free energy of activation, G, that is necessary to force the reactant’s transformation of the reactant to the transition state structure will be determined by using the equation G = H – TS derived from the Eyring plot. Introduction: The purpose of the experiment is to study the rate of reaction through varying concentrations of a catalyst or temperatures with a constant pH, and through the data obtained the rate law, constants, and activation energies can be experimentally determined.
This law, known as Gay-Lussac’s law, observes the relationship between the pressure and temperature of a gas. Contrary to its name, this relationship was actually discovered by French scientific instrument inventor and physicist Guillaume Amontons, and is occasionally referred to Amontons’ Law of Pressure-Temperature. While Guy-Lussac did explore the temperature-pressure relationship, Guy-Lussac’s law is usually used to refer to the law of combining volumes. Amontons stubble across this relationship when he was building an “air thermometer.” Although not many have been able identify his exact method of experimentation, later scientist developed an apparatus in which consisted of pressure gauge and a metal sphere. These two pieces were then attached and submerged in solutions of varying temperatures. From Amontons’ and Guy-Lussac’s research and experimentation, they determined that pressure and volume had direct relationship; as one increased, the other increased. The quotient of pressure and temperature was then found to equal a constant, in which just like Boyle’s law, could be used to find one of the two variables at another pressure or temperature, given one of the variables and that the other conditions remain the same. Instead of using various solutions at different temperatures like in the experiment describe above, many experiments today utilize a solution in which the temperature is increased or decrease, such as in the following
The percentage of NaHCO3 and Na2CO3 calculated from the final unknown test was 77.15% Na2CO3 and 22.85% NaHCO3 (refer to table 3). This was calculated by calibrating an equation in the form of Y = MX + B to the data provided (refer to graph 3). This was able to be done because there was a clear correlation in the data. The greater the amount of NaHCO3, the higher the pressure. When the solution contained 0.2g of Na2CO3, the reaction pressure was 118.45 ka/p, at 0.1g of Na2CO3 and 0.1g of NaHCO3 the pressure was 133.00 ka/p, and at 0.2g of NaHCO3 the pressure was at 146.61. (refer to table 3)
Michael P. Broadribb, C. (2006). Institution of Chemical Engineers . Retrieved July 26, 2010, from IChemE: http://cms.icheme.org/mainwebsite/resources/document/lpb192pg003.pdf
(2)In this paper, we will use Eq. (2) to determine the viscosity with an input of experimental measurements of Pxy and γ.
Using the previously calculated Kf, the molar masses of unknown substances A, C, and D were able to be calculated. However, given that the original Kf was slightly larger than the theoretical value, the molar
So in equation form this is: pV = constant if T is constant Amontons discovered that for a fixed mass of gas at constant volume, the pressure is proportional to the Kelvin temperature. So in equation form this is: p µ T if V is constant Shown below this is represented on graphs in (oC) and (K). [IMAGE] P [IMAGE] [IMAGE] q/oC -273 0 [IMAGE] P 0 T/K Charles discovered that for a fixed mass of gas at constant pressure, the volume is proportional to the Kelvin temperature. So in equation form this is: V µ T if p is constant.
The process of hydrofracking allows for a new source of renewable energy, but it takes a toll on the environment. Five-hundred plus of toxic chemicals like hydrochloric acid, sodium chloride and formic acid are left in the ground. The chemicals produce gases, there...
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Therefore, the relationship between pressure drop and boil-up rate means that more volume of vapour educed per unit time results in more restriction of the holes in the sieve tray and that caused by passing of vapour through the liquid on top of the tray. Hence, the higher the velocity, the higher the boil-up rate and so does the overall pressure drop.
There are five factors which affect the rate of a reaction, according to the collision theory of reacting particles: temperature, concentration (of solution), pressure (in gases), surface area (of solid reactants), and catalysts. I have chosen to investigate the effect of concentration on the rate of reaction. This is because it is the most practical way to investigate. Dealing with temperatures is a difficult task, especially when we have to keep constant high temperatures. Secondly, the rate equation and the constant k changes when the temperature of the reaction changes.
Raoult’s law states that the vapor pressure of one liquid is equal to the product of the vapor pressure of the pure liquid and the mole fraction of that liquid in the liquid. The total vapor pressure is simply the sum of the partial pressures of the two liquid components. Dalton’s law states that the mole fraction of one liquid in the vapor is equal to the partial pressure of the liquid divided by the total pressure. These laws can help explain the process of fractional distillation.
Yen, C.T. and Yu, Y.H. (1966). Mechanics of fluidization. Chemical Engineering Progress Symposium Series, Vol. 62, pp. 100-111.