The expected time to attain chemical equilibrium from a thermodynamic probabilistic analysis

2012 ◽  
Vol 90 (3) ◽  
pp. 243-255
Author(s):  
Christopher Pastore ◽  
Moishe Garfinkle
Keyword(s):  
Experimental Data ◽  
Chemical Reactions ◽  
Chain Mechanism ◽  
Reaction Paths ◽  
Probabilistic Algorithm ◽  
Third Order ◽  
Expected Time ◽  
The Subject ◽  
A Chain ◽  
Stochastic Reaction

Employing a stochastic model, both Planck and Fokker proposed almost a century ago that stoichiometric chemical reactions proceed by a chain mechanism involving discrete reaction steps. To determine whether such a chain mechanism was in fact a valid mechanism for chemical reactions was the subject of a recent study (Garfinkle, M. 2002. J. Phys. Chem. 106A: 490). Using a thermodynamic–probabilistic algorithm the stochastic reaction paths were found to be in excellent agreement with the observed reaction paths plotted from experimental data. This study was then extended to test the conclusions of Ehrenfest and Prigogine that a chain mechanism dictates that the number of discrete reaction steps required for a chemical reaction to attain equilibrium must be finite. The stochastic and empirical reaction paths were compared using experimental data for first-, second-, and third-order reactions as well as fractional order reactions. The empirical verification was excellent.

scholarly journals The photochemistry of phosphine

1932 ◽  
Vol 138 (835) ◽  
pp. 374-395 ◽  
Keyword(s):  
Experimental Data ◽  
Absorption Spectrum ◽  
Photochemical Reactions ◽  
Metallic Elements ◽  
Chain Reaction ◽  
Photo Oxidation ◽  
Considerable Success ◽  
Photochemical Decomposition ◽  
The Subject ◽  
A Chain

Within recent years the spectroscopy and the photochemistry of the hydrides of the non-metallic elements has been the subject of much study and the results explained with considerable success on the basis of the newer theories of photochemical reactions. In spite of the fact that the photochemistry of ammonia has attracted some attention, yet the investigation of the equally simple molecule of phosphine seems to have been entirely neglected. It is with the object of filling this gap in photochemistry that the present experiments have been undertaken. The investigation naturally falls into three parts: ( a ) the absorption spectrum of phosphine, ( b ) the direct photochemical decomposition, ( c ) the photosensitised decomposition. Experimental data on the photo-oxidation are also of importance in view of the fact that the thermal oxidation of phosphine is a chain reaction.

Reactions

2011 ◽  
Author(s):  
Peter Atkins
Keyword(s):  
Chemical Reactions ◽  
Molecular Level ◽  
Chemical Processes ◽  
Chemical Formula ◽  
Complex Processes ◽  
Full Color ◽  
Chemistry Textbooks ◽  
Simple Chemical ◽  
The Subject ◽  
Solid Form

Illustrated with remarkable new full-color images--indeed, one or more on every page--and written by one of the world's leading authorities on the subject, Reactions offers a compact, pain-free tour of the inner workings of chemistry. Reactions begins with the chemical formula almost everyone knows--the formula for water, H2O--a molecule with an "almost laughably simple chemical composition." But Atkins shows that water is also rather miraculous--it is the only substance whose solid form is less dense than its liquid (hence ice floats in water)--and incredibly central to many chemical reactions, as it is an excellent solvent, being able to dissolve gases and many solids. Moreover, Atkins tells us that water is actually chemically aggressive, and can react with and destroy the compounds dissolved in it, and he shows us what happens at the molecular level when water turns to ice--and when it melts. Moving beyond water, Atkins slowly builds up a toolkit of basic chemical processes, including precipitation (perhaps the simplest of all chemical reactions), combustion, reduction, corrosion, electrolysis, and catalysis. He then shows how these fundamental tools can be brought together in more complex processes such as photosynthesis, radical polymerization, vision, enzyme control, and synthesis. Peter Atkins is the world-renowned author of numerous best-selling chemistry textbooks for students. In this crystal-clear, attractively illustrated, and insightful volume, he provides a fantastic introductory tour--in just a few hundred colorful and lively pages - for anyone with a passing or serious interest in chemistry.

In Reply: Combinations of Antibiotics

PEDIATRICS ◽  
1960 ◽  
Vol 26 (3) ◽  
pp. 499-499
Author(s):  
Robert J. Haggerty
Keyword(s):  
Experimental Data ◽  
Clinical Data ◽  
Experimental Work ◽  
The Subject ◽  
Antimicrobial Combinations

I am delighted to have Dr. Jawetz again bring to the attention of your readers his definitive work on the subject of antimicrobial combinations. We certainly have no quarrel with the points he reiterates. Our choice of words, "It is not clear why these results are at variance with the experimental data of Jawetz or the clinical data of Lepper and Dowling," was probably unfortunate, for Dr. Jawetz points out why the results did differ from his experimental work.

Modified methodology of computation of admissible continuous currents of plain conductors of overhead transmission lines and catenaries

2021 ◽  
Vol 2 (2) ◽  
pp. 36-43
Author(s):  
Evgeniy P. FIGURNOV ◽  
◽  
Yury I. ZHARKOV ◽  
Valeriy I. KHARCHEVNIKOV ◽  
◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Transmission Lines ◽  
Power Transmission ◽  
Convection Heat Transfer ◽  
Heating And Cooling ◽  
Continuous Current ◽  
The Subject ◽  
The Common ◽  
Overhead Power Transmission Line

Methodology provided summarizes published, original and foreign theoretic and experimental data on the subject of heating and cooling of standard and shaped conductors of overhead power transmission line and uses those of them which are most affected to fundamental heat-transfer laws. Computation surface area of standard and shaped wire formulas are given. The common formula of convection heat transfer coefficient is provided, based on wind speed and direction, concerning antiicing mode. Parameters of this formula do not coincide with those existing, as they are based on experimental data on standard and shaped conductors but not on round tubes. Formula of computation of heat transfer power under the influence of solar radiation is given. Summarized formula of admissible continuous current computation is given, all the components have detailed description in the article.

THE KINETICS OF THE OXIDATION OF GASEOUS ACETALDEHYDE

1932 ◽  
Vol 7 (2) ◽  
pp. 149-161 ◽  
Author(s):  
W. H. Hatcher ◽  
E. W. R. Steacie ◽  
Frances Howland
Keyword(s):  
Carbon Dioxide ◽  
Formic Acid ◽  
Induction Period ◽  
Reaction Vessel ◽  
Oxidation Products ◽  
Main Reaction ◽  
Chain Mechanism ◽  
Subsequent Reaction ◽  
A Chain ◽  
Kinetics Of

The kinetics of the oxidation of gaseous acetaldehyde have been investigated from 60° to 120 °C. by observing the rate of pressure decrease in a system at constant volume. A considerable induction period exists, during which the main products of the reaction are carbon dioxide, water, and formic acid. The main reaction in the subsequent stages involves the formation of peroxides and their oxidation products. The heat of activation of the reaction is 8700 calories per gram molecule. The indications are that the reactions occurring during the induction period are heterogeneous. The subsequent reaction occurs by a chain mechanism. The chains are initiated at the walls of the reaction vessel, and are also largely broken at the walls.

Réactions ion–molécule dans les méthylbutènes: radiolyse du méthane

1976 ◽  
Vol 54 (4) ◽  
pp. 555-559
Author(s):  
Guy J. Collin
Keyword(s):  
Tertiary Structure ◽  
Ionic Mechanism ◽  
Chain Mechanism ◽  
A Chain

The radiolysis of gaseous methane has been studied in the presence of one of the three methylbutenes. We have observed an important isomerization of the added olefin. An ionic mechanism initiated by the CH5+ and C2H5+ ions seems to be compatible with the observations reported. Isomerization proceeds through a chain mechanism where the chain carrier may be the tert-C5H11+ ion. In the presence of 3-methyl-1-butene, the initially formed (CH3)2CHCHCH3+ ion isomerizes to the tertiary structure before producing the observed isomerization.

scholarly journals Application of descriptive statistics in analysis of experimental data

2008 ◽  
Vol 62 (1-2) ◽  
pp. 85-95
Author(s):  
Milorad Mirilovic ◽  
Ivana Pejin
Keyword(s):  
Experimental Data ◽  
Statistical Analysis ◽  
Standard Deviation ◽  
Arithmetic Mean ◽  
Descriptive Statistics ◽  
Qualitative Investigation ◽  
Scientific Methods ◽  
The Subject ◽  
Variation Interval ◽  
Descriptive Statistical Analysis

Statistics today represent a group of scientific methods for the quantitative and qualitative investigation of variations in mass appearances. In fact, statistics present a group of methods that are used for the accumulation, analysis, presentation and interpretation of data necessary for reaching certain conclusions. Statistical analysis is divided into descriptive statistical analysis and inferential statistics. The values which represent the results of an experiment, and which are the subject of observation of a certain occurrence, are called parameters and they are divided into descriptive and numerical. All numerical parameters are divided into non-continuous and continuous. The graphic presentation of the distribution of frequencies can be by poligon or histogram. The most frequently applied descriptive statistical methods are: arithmetic mean, standard deviation, standard error of arithmetic mean, variation coefficient, and variation interval.

Sign in / Sign up

Export Citation Format

Share Document