Many translated example sentences containing “enfriamiento adiabático” – English-Spanish dictionary o Calorímetro Adiabático de Seguimiento de Presión [. adiabático adjective, masculine (adiabática f sl, adiabáticos m pl, Resfriamento Adiabático, o qual aumenta [ ] Calorímetro Adiabático tem se tornado [ ]. Glossaries for translators working in Spanish, French, Japanese, Italian, etc. Glossary translations.
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Numerical approach and experimental data. The signal produced by a pseudo-adiaba-tic calorimeter is simulated by numerical solution of the differential equations that model the chemical kinetics , the ther-mal properties of the calorimetric cell , and the response of the thermistor used as a thermometric sensor .
These equations show that the calorimetric signal is related with concentration in a complex way. In order to help understanding this relation-ship, the initial rate method was applied to the simulated data to assess the rela-tionship between the order and the kine-tic constants calculated with those used for the simulations. As it was expected, the initial rate method for the calorime-tric data, do not give a slope directly re-lated with the order of the reaction, as it would be produced, for example, in data from a spectrophotometer.
However, a linear relationship was found between what we call the “calorimetric order” and the kinetic order. Thermokinetics, pseudo-adiabatic calorimeter, zero, first and second order kinetics, simulations, H 2 O 2 decomposition.
Adiabatisches Kalorimeter – calorímetro adiabático – personal glossaries
Solution calorimetry is used to obtain thermodynamic information about che-mical processes 1, 2, 3. It is clear, that the kinetic information is inside the ca-lorimetric data, but it is not so easy or at least not so commonto obtain that information 4, 5. This paper presents an approach to obtain kinetic information from the calorimetric data.
The simulated data were treated using the well caloimetro kinetic method of initial rates to achieve the order and the kinetic constants of the processes 7. After the comparison, it was possible to construct a linear relationship between the kinetic order of the reaction and what we cali the adiabatkco order” of the reaction found by the initial rate method apply directly to the calorimetric data.
A Dewar fask was used as a calorimetric cell, and it was submerged in a water thermostat. The whole system was inside an air thermostat. The solutions used for the experiments where inside the air thermostat contained in vessels, as it is showed in Figure 1.
Additional details of the calorimeter can be seen in reference 6. All reagents used were of analytical grade. Adequate dilutions were used to obtain the required concentrations. Two solutions were mixed to start the reaction using the dispositive show in the center of Figure 1numeral b.
Meaning of “adiabático” in the Spanish dictionary
The simulations were made by solving, numerically, a system of three coupled differential equations. The first one comes from the general chemical reaction:. Where [A] is the concentration of the reagent A, t is time, and k i. The second equation represents the calorimetric cell behavior:. The third equation represents the behavior of the thermistor used as a sensor:.
Table 1 pre-sents the numerical values of the parameters used for simulations. These adiabaticco were found by a simplex optimization process where a calibration reaction, the neutralization of NaOH with HCl, was simulated, and the results were adjusted changing the adiabztico of table 1until the agreement between the experimental data and calorietro simulated calorimetrl was trust-worthy 6. The simulations show the clear effect of the kinetic order of the reaction over the calorimetric signal when the calorimetor rate parameter k and the initial concentration A 0 are constant, Figure 2.
In Figure 3athe kinetic order of the reaction is generalized to any number possible between 2 and A nice sequence, from 2 to almost 0. Figure 3b try to describe this issue in a most tangible way. Figure 3b is an expansion of Figure 3a. The initial rate method. The initial rate method was used to determine the kinetic order of the reaction from calorimetric data. Simulated data for 8 kinetics orders between 0. At each order, five different initial concentrations were used 0. Figure 4a shows an example for the case of first order, and Figure 4bshows an enlargement of these simulated results.
These fgures caalorimetro the set of data that we used to obtain the kinetic information from the calorimetric measurements.
The initial rate method was applied to the simulated calorimetric data, and then, we were able to obtain asiabatico relationship bet-ween the kinetic adiabattico of the reaction, and that we call “the calorimetric order”, Figure 5. The ideal relationship would be a straight line with slope equal to one and intercept equal to zero; instead, a straight line with slope different to one and in-tercept different to zero was obtained.
Adiabaico, this relationship is particularly useful to obtain the kinetic order of the reaction from the calorimetric data, and it can be used to obtain that information from experimental calorimetric results as we will discuss in the next part of this paper.
It is important to notice, before to follow with the experimental data, that the “calorimetric order” it is not equal to the “kinetic order” because the signal in ccalorimetro, the right hand side of the equation , has more calotimetro one term, and then the slope of the log-log plot of the calorimetric data is adiiabatico the kinetic order of the reaction. The experimental data was compared with the simulations for different orders fnding that the overall pro-cess is a clear second order, Figure 6.
Observe the slope of the log-log plot, figure 7and compare it with Figure 5. Adabatico interpolation of the “calorimetric order”, 1. The ex-periment was made at constant concentration of H 2 0 2 0. In this case, the slope of the log-log plot was 0. It must be said that these two processes of catalyzed decomposi-tion of the H 2 0 2 are complex; specially the heterogeneous one.
Then, the kinetic information, obtained from calorimetric data is, also, the adiabaticoo information of the total process, and afiabatico order of reaction is for the global process of decomposition of H 2 O 2including any changes of the surface or any other process involved Finally, as a way to control the whole process, and calorumetro it is a calibration reaction for the calorimeter, too; the neutralization reaction of NaOH with HCl was studied.
The results showed a second order for the kinetics which is what it is expected, and a reasonable agreement in the value of the kinetic constant. Howe-ver, it is necessary to mention that, due to the huge value of the second order constant of the neutralization process, it is not possible to obtain a clear distinction between zero, first or second order reactions, when the calorimeter data are taken at intervals of 1 second, as it was the case in the calorimeter used for this work.
In this case, to see the difference in the calorimetric signal as a function of the kinetic order, it is necessary to collect data at time intervals in the range of the inverse of the kinetic constant of the reaction, it means at intervals around of 10 seconds.
This is a warning, because the procedure to obtain the kinetic order of the reaction works only adiabaticl the kinetic constant of the process under investigation, has a value that generate data in a scale of time longer than the time scale of data acquisition. An easy way to relate, what we call, ca,orimetro “calorimetric order”, with the kinetic order of the reaction was presented.
The relationship was resumed in a linear equation, and it was used to obtain the kinetic order of three experimental processes: The latter reaction is used as a patron in ca-lorimetry, and in this case, it was helpful to control the entire procedure, allowing to establish a limit to the applicability of the protocol developed, particularly with respect to the magnitude of the kinetic constant calorimetri the studied reaction.
Services on Demand Article. English pdf Article in xml format Article references How to cite this article Automatic translation Send adiabayico article by e-mail. Reagents and calorimetric experiments All reagents used were of analytical grade. Simulations The simulations were made by solving, numerically, a system of three coupled differential equations.
The first one comes from the general chemical reaction: The second equation represents the calorimetric cell behavior: The third equation represents the behavior of the thermistor used as a sensor: This can be approximated as: Equation  is a second order reaction.
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calorímetro | Spanish to English Translation – Oxford Dictionaries
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