This document reports on a study that determined densities of solutions containing N-methyl formamide (NMF) and dimethyl formamide (DMF) solvent mixtures at 250°C using a magnetic float densitometer. Densities were measured for the solvent mixtures with 0%, 25%, 50%, 75%, and 100% NMF. Apparent molar volumes (φv) were calculated from the density data and plotted against the square root of concentration (√C) for tetraalkylammonium iodide salts (Et4NI, Pr4NI, Bu4NI, Pen4NI) dissolved in the mixtures. The slopes (Sv) of the φv-√C curves were positive for solutions in pure
This document presents a kinetic method for determining microquantities of D(-)-arabinose. The method relies on D(-)-arabinose accelerating the reaction between molybdenum(VI) and hydrogen peroxide in a 50% acetonitrile solution. Optimal experimental conditions were determined by studying the kinetics of this reaction with and without D(-)-arabinose. D(-)-Arabinose concentrations from 46 to 135 μg/ml were determined photometrically by measuring the rate of colored product formation. The standard deviation was less than 10%. This kinetic method allows for the determination of microquantities of D(-)-arabinose.
Microchimica Acta Volume 69 issue 3-4 1978 [doi 10.1007_bf01201734] M. A. Sek...Sekheta Bros Company
This document describes kinetic methods for determining ultramicro quantities of manganese(II), molybdenum(VI), and tungsten(VI) based on their catalytic effect on the oxidation of Azorubin S by hydrogen peroxide. The methods were found to determine these elements in the concentration ranges of 5.5-33 ng/ml for manganese, 1.3-8.1 μg/ml for molybdenum, and 5.9-44.1 μg/ml for tungsten, with relative standard deviations less than 11%, 9%, and 5% respectively. The oxidation reactions were determined to be first order with respect to the catalyst and zero order with respect to Azor
This document describes Marco Mazza's research using the Flamelet-Generated Manifold (FGM) method to model turbulent non-premixed flames in OpenFOAM 2.1.1. The FGM method involves generating a manifold of 1D flamelet solutions for different control variables like mixture fraction. These manifolds can then be used in CFD simulations by looking up thermochemical states based on the control variables. Mazza first sets up the simulation of a non-premixed jet flame and analyzes cold flow results. He then incorporates a 1D manifold without combustion before expanding to a 2D manifold with combustion chemistry included. Results are analyzed and compared to experimental data.
Microchimica Acta Volume 75 issue 3-4 1981 [doi 10.1007_bf01196393] G. A. Mil...Sekheta Bros Company
This study presents a kinetic method for determining ultramicro quantities of serotonin, 5-hydroxyindolacetic acid, L-dopa, methyldopa, and carbidopa. The method involves reacting these compounds with molybdenum and hydrogen peroxide in a carbonate buffer to form colored products. Kinetic expressions were derived relating the rate of color formation to concentrations of reactants. Optimal conditions were determined and calibration curves showed the method could determine concentrations of the compounds down to the picogram per milliliter level with good precision. Interference studies found most other substances did not interfere at levels above those of the analytes. This sensitive and simple kinetic method is suitable for analyzing these physiologically important
Partial gibbs free energy and gibbs duhem equationSunny Chauhan
Partial gibbs free energy and gibbs duhem equation,relation between binary solution,relation between partiaL properties,PARTIAL PROPERTIES,PARTIAL PROPERTIES IN BINARY SOLUTION,RELATIONS AMONG PARTIAL PROPERTIES,Maxwell relation,Examples
1) A kinetic method is proposed for the determination of uranium(VI) based on its catalytic action on the decomposition of hydrogen peroxide in alkaline media.
2) The method was optimized and the kinetic expression was derived. Uranium(VI) can be determined in the concentration range of 0.8 to 6.4 μg/ml using the tangent method.
3) The method is selective and enables determination of uranium(VI) in the presence of high concentrations of various interfering ions. It was applied to determine uranium in phosphoric acid and phosphate ores with results matching another method.
Microchimica Acta Volume 84 issue 5-6 1984 [doi 10.1007_bf01197162] G. A. Mil...Sekheta Bros Company
This document describes a kinetic method for determining morphine concentration in urine samples. The method involves reacting morphine in the sample with hydrogen peroxide and cobalt(II) ions to form a colored compound. The rate of decomposition of this compound is measured photometrically and is directly proportional to the concentration of morphine over a certain range. The method was found to accurately determine morphine concentrations from 1.5 to 12.3 μg/ml in urine samples. It was also applied to analyze urine samples from individuals suspected of taking morphine or heroin and the results correlated well with an established HPLC method.
This study investigated the polymerization of lactic acid as a model for prebiotic peptide formation via ester-amide exchange. Lactic acid was polymerized in a closed system at 85°C over various time points. HPLC and 1H-NMR were used to analyze the polymers and determine degree of polymerization (DP) and total lactic acid units. DP was found to increase with time while total units decreased, showing polymer regeneration. Methods showed consistent results within 10-15% error. Further studies will compare kinetics to a computer simulation to determine rate constants and model polymerization from various monomers.
This document presents a kinetic method for determining microquantities of D(-)-arabinose. The method relies on D(-)-arabinose accelerating the reaction between molybdenum(VI) and hydrogen peroxide in a 50% acetonitrile solution. Optimal experimental conditions were determined by studying the kinetics of this reaction with and without D(-)-arabinose. D(-)-Arabinose concentrations from 46 to 135 μg/ml were determined photometrically by measuring the rate of colored product formation. The standard deviation was less than 10%. This kinetic method allows for the determination of microquantities of D(-)-arabinose.
Microchimica Acta Volume 69 issue 3-4 1978 [doi 10.1007_bf01201734] M. A. Sek...Sekheta Bros Company
This document describes kinetic methods for determining ultramicro quantities of manganese(II), molybdenum(VI), and tungsten(VI) based on their catalytic effect on the oxidation of Azorubin S by hydrogen peroxide. The methods were found to determine these elements in the concentration ranges of 5.5-33 ng/ml for manganese, 1.3-8.1 μg/ml for molybdenum, and 5.9-44.1 μg/ml for tungsten, with relative standard deviations less than 11%, 9%, and 5% respectively. The oxidation reactions were determined to be first order with respect to the catalyst and zero order with respect to Azor
This document describes Marco Mazza's research using the Flamelet-Generated Manifold (FGM) method to model turbulent non-premixed flames in OpenFOAM 2.1.1. The FGM method involves generating a manifold of 1D flamelet solutions for different control variables like mixture fraction. These manifolds can then be used in CFD simulations by looking up thermochemical states based on the control variables. Mazza first sets up the simulation of a non-premixed jet flame and analyzes cold flow results. He then incorporates a 1D manifold without combustion before expanding to a 2D manifold with combustion chemistry included. Results are analyzed and compared to experimental data.
Microchimica Acta Volume 75 issue 3-4 1981 [doi 10.1007_bf01196393] G. A. Mil...Sekheta Bros Company
This study presents a kinetic method for determining ultramicro quantities of serotonin, 5-hydroxyindolacetic acid, L-dopa, methyldopa, and carbidopa. The method involves reacting these compounds with molybdenum and hydrogen peroxide in a carbonate buffer to form colored products. Kinetic expressions were derived relating the rate of color formation to concentrations of reactants. Optimal conditions were determined and calibration curves showed the method could determine concentrations of the compounds down to the picogram per milliliter level with good precision. Interference studies found most other substances did not interfere at levels above those of the analytes. This sensitive and simple kinetic method is suitable for analyzing these physiologically important
Partial gibbs free energy and gibbs duhem equationSunny Chauhan
Partial gibbs free energy and gibbs duhem equation,relation between binary solution,relation between partiaL properties,PARTIAL PROPERTIES,PARTIAL PROPERTIES IN BINARY SOLUTION,RELATIONS AMONG PARTIAL PROPERTIES,Maxwell relation,Examples
1) A kinetic method is proposed for the determination of uranium(VI) based on its catalytic action on the decomposition of hydrogen peroxide in alkaline media.
2) The method was optimized and the kinetic expression was derived. Uranium(VI) can be determined in the concentration range of 0.8 to 6.4 μg/ml using the tangent method.
3) The method is selective and enables determination of uranium(VI) in the presence of high concentrations of various interfering ions. It was applied to determine uranium in phosphoric acid and phosphate ores with results matching another method.
Microchimica Acta Volume 84 issue 5-6 1984 [doi 10.1007_bf01197162] G. A. Mil...Sekheta Bros Company
This document describes a kinetic method for determining morphine concentration in urine samples. The method involves reacting morphine in the sample with hydrogen peroxide and cobalt(II) ions to form a colored compound. The rate of decomposition of this compound is measured photometrically and is directly proportional to the concentration of morphine over a certain range. The method was found to accurately determine morphine concentrations from 1.5 to 12.3 μg/ml in urine samples. It was also applied to analyze urine samples from individuals suspected of taking morphine or heroin and the results correlated well with an established HPLC method.
This study investigated the polymerization of lactic acid as a model for prebiotic peptide formation via ester-amide exchange. Lactic acid was polymerized in a closed system at 85°C over various time points. HPLC and 1H-NMR were used to analyze the polymers and determine degree of polymerization (DP) and total lactic acid units. DP was found to increase with time while total units decreased, showing polymer regeneration. Methods showed consistent results within 10-15% error. Further studies will compare kinetics to a computer simulation to determine rate constants and model polymerization from various monomers.
Chromatography is a technique used to separate mixtures by distributing components between a stationary and mobile phase. Separation occurs as components interact differently with the phases and move through a column at different rates. Key terms include retention time, plate number, and resolution which characterize separation efficiency. Variables like particle size, temperature, flow rate, and column length affect efficiency by influencing how components partition between phases.
13C NMR Derived Average Molecules - Heavy Petroleum - ISMAR 2013John Edwards
This document describes a new NMR method for analyzing heavy petroleum hydrocarbons using combined 13C NMR and DEPT-45 experiments. The method allows bridgehead aromatic and protonated aromatic carbons to be distinguished, improving the accuracy of calculated molecular parameters like average aromatic ring size. Previous studies had underestimated ring size, but results using this new method agree with other analytical techniques that aromatic rings are on average 5-7 instead of 3-4. The combined NMR experiments provide quantitative information about carbon types and molecular structure of asphaltenes.
Inhibitory Effect of Some Carbazides on Corrosion of Aluminium in Hydrochloric Acid and Sodium Hydroxide Solutions
The dissolution of aluminium in hydrochloric acid and sodium hydroxide solutions in the presence of semicarbazide, thiosemicar- bazide and sym.dipheny1carbazide as corrosion inhibitors has been studied using thermometric, weight-loss and polarization methods. The three methods gave consistent results. The higher inhibition efficiency of these compounds in acidic than in alkaline madia may be due to the less negative potential of aluminium in hydrochloric acid solution, favouring adsorption of the additive.The adsorption of these compounds were found to obey Frurnkin adsorption isotherm. Cathodic polarization measurements showed that these com- pounds are cathodic inhibitors and their adsorption in the double layer does not change the mechanism of the hydrogen evolution reaction. The results are analysed in terms of both molecular and cationic adsorption.
Analysis of Transport Properties and Acoustical Parameters of Sulphanilamide ...IOSR Journals
Sulphanilamide is the parent compound of all the sulpha-durgs which is important in urinary tract infections and meningococcal meningitis profilaxes. Ultrasonic velocity measurements are highly sensitive to molecular interactions and used to provide qualitative informations about the physical nature and strength of the molecular ∕inter-ionic interactions. In the present work, non-aqueous solutions of Sulphanilamide have been prepared with different concentrations and the experiments were carried out from a low temperature of 50c to a high temperature of 550c. The ultrasonic velocity data combined with density and viscosity provides the standard means for determining the internal pressure, free volume and acoustical parameters. The various interactions occurring in the solutions are interpreted interms of ion-ion and ion-solvent interactions. An attempt is made to identify the entry of solvate into the samples and the entry of drug molecules into the solvate which supports to identify the molecular structure.
Titration is a quantitative analysis technique used to determine the concentration of an unknown solution. It involves adding a titrant of known concentration to the analyte until the reaction is complete, as indicated by an endpoint. The volume of titrant used can then be used to calculate the concentration of the analyte based on the chemical reaction between them. Common types of titrations include acid-base titrations, complexometric titrations, redox titrations, and precipitation titrations.
Cooperative learning in science education is addressed in this article. How students use a very relevant topic of anti-cancer agents, and the novel technique of (Heteronuclear single Quantum Correllation Spectroscopy )2D -HSQC FT-NMR to organize spectra data is shown. Here, undergraduates become familiar with making plots of 1H FT-NMR and 13C FT-NMR , learning FT-NMR data processing (spinworks) and also use Chemdraw NMR to present data take with a Varian 600 MHz FT-NMR spectrometer.
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
1) The document discusses volumetric analysis, which is a quantitative chemical analysis method that involves titration. It is defined as determining the concentration of an unknown solution by titrating a known volume of it with a solution of known concentration.
2) Key terms in volumetric analysis are discussed, including titration, titrant, equivalence point, indicator, end point, and titration error.
3) Requirements for volumetric analysis are that the reaction must be complete, stoichiometric, relatively fast, and have a detectable physical or chemical change at the equivalence point that can be identified using an indicator.
This document discusses the principles and procedures of volumetric analysis. Volumetric analysis involves titrating an analyte of unknown concentration with a titrant using an indicator to mark the endpoint. The key types of titrations used are acid-base, oxidation-reduction, precipitation, and complex formation titrations. Methods of volumetric analysis include direct titration, back titration, and replacement titration. The equivalence point represents complete reaction between analyte and titrant while the endpoint is the visual change in the indicator.
Kinetics of Ruthenium(III) Catalyzed and Uncatalyzed Oxidation of Monoethanol...Ratnakaram Venkata Nadh
Kinetics of uncatalyzed and ruthenium(III) catalyzed oxidation of monoethanolamine by N-bromosuccinimide
(NBS) has been studied in an aqueous acetic acid medium in the presence of sodium acetate
and perchloric acid, respectively. In the uncatalyzed oxidation the kinetic orders are: the first order in NBS,
a fractional order in the substrate. The rate of the reaction increased with an increase in the sodium acetate
concentration and decreased with an increase in the perchloric acid concentration. This indicates that free
amine molecules are the reactive species. Addition of halide ions results in a decrease in the kinetic rate,
which is noteworthy. Both in absence and presence of a catalyst, a decrease in the dielectric constant of the
medium decreases the kinetic rate pointing out that these are dipole—dipole reactions. A relatively higher
oxidation state of ruthenium i.e., Ru(V) was found to be the active species in Ru(III) catalyzed reactions. A
suitable mechanism consistent with the observations has been proposed and a rate law has been derived to
explain the kinetic orders.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle is that a titrant of known concentration is added from a burette to the analyte until the chemical reaction between them is complete. Titration relies on acid-base, precipitation, complexometric, or redox reactions and is indicated by color changes from an indicator. It is a widely used analytical technique due to its accuracy, speed, low cost, and simplicity.
This document provides an introduction and overview of analytical chemistry concepts:
- Analytical chemistry involves separating, identifying, and determining the relative amounts of compounds in a sample. It has two main parts: qualitative analysis to identify what is present, and quantitative analysis to determine how much is present.
- Important units of measurement in analytical chemistry include grams, milligrams, microliters, and the mole. A mole represents 6.02x1023 units of a substance and is used to relate amounts of substances.
- Calculations involving moles and millimoles allow determining the amount of a substance in a sample based on its mass, molar mass, and the chemical formula. Factor-label and dimensional analysis
Presentation 2 chemistry , volumetric analysis A to ZTejNarayan15
1) The document discusses key concepts in chemistry including equivalent weight, volumetric analysis, titration, indicators, and methods of expressing concentration.
2) It provides examples of different types of titrations and selecting suitable indicators based on the pH curve for different acid-base reactions.
3) Formulas for normality, molarity and other concentration units are defined along with examples of calculating concentration from given values.
This document discusses different types of titrimetry including volumetric, coulometric, and gravimetric titrimetry. It describes key concepts in titrimetric analysis including standard solutions, equivalence points, end points, titration curves, and sources of error. Specific techniques are covered such as back titration, precipitation titrimetry using silver nitrate, and different types of indicators that can be used for argentometric (silver-based) titrations including chromate, fluorescein, and iron (III). Diagrams illustrate the titration process and how curves are affected by concentration and reaction completeness.
simple, sensitive, precise, accurate, highly reproducible and economical, visible spectrophotometric
method for the determination lurasidone in bulk form was developed and validated. The method is
based on the formation of an oxidative coupling product by the reaction of lurasidone with 3-methylbenzothiazolin-
2-one hydrazone as a chromogenic reagent in presence of ferric chloride. The linear regression
analysis data for the calibration plot showed good linear relationship within the concentration range of 0–
100 μg/mL with a correlation coefficient (r) value of 0.9997. The limits of detection and quantitation are 0.6
and 1.7 μg/mL, respectively. The method was tested and validated according to ICH guidelines. The results
demonstrated that the procedure is accurate, precise and reproducible (RSD < 2%).
Quantitative analysis and volumetric analysisMussaOmary3
This document provides information on quantitative analysis and volumetric analysis techniques. It defines key terms like concentration, molarity, and standard solutions. It describes common volumetric apparatus and how to perform acid-base titrations using appropriate indicators. It also covers concepts like molar ratios, dilution calculations, and determining water of crystallization through titration reactions. The document provides examples of calculations for molarity, concentration, purity, and molar mass determinations.
The document discusses chemical kinetics and reaction rates. It provides information on:
- The study of rates of chemical reactions and reaction mechanisms (chemical kinetics).
- How reaction rates are expressed in terms of changes in reactant/product concentrations over time.
- Factors that influence reaction rates such as concentration, temperature, and surface area.
- Collision theory and how effective collisions between reactant particles lead to reactions.
- Reaction orders, rate laws, and how to determine the order of reactions based on experimental rate data.
There is a global acceptance that out of the initial oil in place a maximum of about one third can be recovered by relying on depletion drive energy from the petroleum reservoir. To recover additional resources the depleted energy of the reservoir must be boosted. The usual approach involves water flooding and to maximize recovery under these conditions a sound knowledge of multiphase flow in porous media is required. Relative permeability is a fundamental multiphase flow function that has received immense attention in the petroleum industry. In this regard, a new model of water relative permeability based on resistivity measurement has been developed by Li (2004). He compared his relative permeability data to that obtained using the centrifuge. It was found to show close agreement.
This study was conducted with two primary objectives. The first was to compare the new model relative permeability to the widely used unsteady state relative permeability data using a Benchtop Relative Permeameter (BRP 350). The second was to investigate the sensitivity of the new model to brine salinity. The experiment was conducted at ambient conditions with different brine concentrations ranging from 2% to 10%. Results show that the new model predicts relative permeability similar to the Benchtop Relative Permeameter (BRP 350) at lower brine concentration (2%) and at higher brine concentration (4.5% and 10%) close agreement is perceived only at lower water saturations. In addition, the new model has been found not to be sensitive to salinity at lower brine concentration (2% NaCl – 4.5% NaCl) and found to be sensitive at higher brine concentration (10% NaCl).
This document summarizes a study on the spectroscopic and micellization properties of uranyl hexanoate in organic solvents. Infrared spectroscopy revealed that uranyl hexanoate has partial ionic character, with the fatty acids existing in a dimeric state through hydrogen bonding. Conductometric measurements determined the critical micellar concentration of uranyl hexanoate in DMF to be 0.03M. The addition of Sudan dye increased conductivity but did not change the critical micellar concentration. Uranyl hexanoate behaved as a simple electrolyte below the critical micellar concentration.
Accurate Solvent – Solvent Densities, Dielectric Constants and Volumes of ...Scientific Review SR
In this paper the densities and dielectric constants for mixed (DMF) – water solvents at 298.15K were
accurately measured using densimeter DMA-58 and decameter DK-300 respectively. Different volumes (molar
volume V
M, Van der Waals volume V
W, electrostriction volume V e and crystal volume VC) for mixed (DMF) –
H2O solvents were evaluated from density measurements
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Chromatography is a technique used to separate mixtures by distributing components between a stationary and mobile phase. Separation occurs as components interact differently with the phases and move through a column at different rates. Key terms include retention time, plate number, and resolution which characterize separation efficiency. Variables like particle size, temperature, flow rate, and column length affect efficiency by influencing how components partition between phases.
13C NMR Derived Average Molecules - Heavy Petroleum - ISMAR 2013John Edwards
This document describes a new NMR method for analyzing heavy petroleum hydrocarbons using combined 13C NMR and DEPT-45 experiments. The method allows bridgehead aromatic and protonated aromatic carbons to be distinguished, improving the accuracy of calculated molecular parameters like average aromatic ring size. Previous studies had underestimated ring size, but results using this new method agree with other analytical techniques that aromatic rings are on average 5-7 instead of 3-4. The combined NMR experiments provide quantitative information about carbon types and molecular structure of asphaltenes.
Inhibitory Effect of Some Carbazides on Corrosion of Aluminium in Hydrochloric Acid and Sodium Hydroxide Solutions
The dissolution of aluminium in hydrochloric acid and sodium hydroxide solutions in the presence of semicarbazide, thiosemicar- bazide and sym.dipheny1carbazide as corrosion inhibitors has been studied using thermometric, weight-loss and polarization methods. The three methods gave consistent results. The higher inhibition efficiency of these compounds in acidic than in alkaline madia may be due to the less negative potential of aluminium in hydrochloric acid solution, favouring adsorption of the additive.The adsorption of these compounds were found to obey Frurnkin adsorption isotherm. Cathodic polarization measurements showed that these com- pounds are cathodic inhibitors and their adsorption in the double layer does not change the mechanism of the hydrogen evolution reaction. The results are analysed in terms of both molecular and cationic adsorption.
Analysis of Transport Properties and Acoustical Parameters of Sulphanilamide ...IOSR Journals
Sulphanilamide is the parent compound of all the sulpha-durgs which is important in urinary tract infections and meningococcal meningitis profilaxes. Ultrasonic velocity measurements are highly sensitive to molecular interactions and used to provide qualitative informations about the physical nature and strength of the molecular ∕inter-ionic interactions. In the present work, non-aqueous solutions of Sulphanilamide have been prepared with different concentrations and the experiments were carried out from a low temperature of 50c to a high temperature of 550c. The ultrasonic velocity data combined with density and viscosity provides the standard means for determining the internal pressure, free volume and acoustical parameters. The various interactions occurring in the solutions are interpreted interms of ion-ion and ion-solvent interactions. An attempt is made to identify the entry of solvate into the samples and the entry of drug molecules into the solvate which supports to identify the molecular structure.
Titration is a quantitative analysis technique used to determine the concentration of an unknown solution. It involves adding a titrant of known concentration to the analyte until the reaction is complete, as indicated by an endpoint. The volume of titrant used can then be used to calculate the concentration of the analyte based on the chemical reaction between them. Common types of titrations include acid-base titrations, complexometric titrations, redox titrations, and precipitation titrations.
Cooperative learning in science education is addressed in this article. How students use a very relevant topic of anti-cancer agents, and the novel technique of (Heteronuclear single Quantum Correllation Spectroscopy )2D -HSQC FT-NMR to organize spectra data is shown. Here, undergraduates become familiar with making plots of 1H FT-NMR and 13C FT-NMR , learning FT-NMR data processing (spinworks) and also use Chemdraw NMR to present data take with a Varian 600 MHz FT-NMR spectrometer.
International Journal of Pharmaceutical Science Invention (IJPSI) is an international journal intended for professionals and researchers in all fields of Pahrmaceutical Science. IJPSI publishes research articles and reviews within the whole field Pharmacy and Pharmaceutical Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
1) The document discusses volumetric analysis, which is a quantitative chemical analysis method that involves titration. It is defined as determining the concentration of an unknown solution by titrating a known volume of it with a solution of known concentration.
2) Key terms in volumetric analysis are discussed, including titration, titrant, equivalence point, indicator, end point, and titration error.
3) Requirements for volumetric analysis are that the reaction must be complete, stoichiometric, relatively fast, and have a detectable physical or chemical change at the equivalence point that can be identified using an indicator.
This document discusses the principles and procedures of volumetric analysis. Volumetric analysis involves titrating an analyte of unknown concentration with a titrant using an indicator to mark the endpoint. The key types of titrations used are acid-base, oxidation-reduction, precipitation, and complex formation titrations. Methods of volumetric analysis include direct titration, back titration, and replacement titration. The equivalence point represents complete reaction between analyte and titrant while the endpoint is the visual change in the indicator.
Kinetics of Ruthenium(III) Catalyzed and Uncatalyzed Oxidation of Monoethanol...Ratnakaram Venkata Nadh
Kinetics of uncatalyzed and ruthenium(III) catalyzed oxidation of monoethanolamine by N-bromosuccinimide
(NBS) has been studied in an aqueous acetic acid medium in the presence of sodium acetate
and perchloric acid, respectively. In the uncatalyzed oxidation the kinetic orders are: the first order in NBS,
a fractional order in the substrate. The rate of the reaction increased with an increase in the sodium acetate
concentration and decreased with an increase in the perchloric acid concentration. This indicates that free
amine molecules are the reactive species. Addition of halide ions results in a decrease in the kinetic rate,
which is noteworthy. Both in absence and presence of a catalyst, a decrease in the dielectric constant of the
medium decreases the kinetic rate pointing out that these are dipole—dipole reactions. A relatively higher
oxidation state of ruthenium i.e., Ru(V) was found to be the active species in Ru(III) catalyzed reactions. A
suitable mechanism consistent with the observations has been proposed and a rate law has been derived to
explain the kinetic orders.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle is that a titrant of known concentration is added from a burette to the analyte until the chemical reaction between them is complete. Titration relies on acid-base, precipitation, complexometric, or redox reactions and is indicated by color changes from an indicator. It is a widely used analytical technique due to its accuracy, speed, low cost, and simplicity.
This document provides an introduction and overview of analytical chemistry concepts:
- Analytical chemistry involves separating, identifying, and determining the relative amounts of compounds in a sample. It has two main parts: qualitative analysis to identify what is present, and quantitative analysis to determine how much is present.
- Important units of measurement in analytical chemistry include grams, milligrams, microliters, and the mole. A mole represents 6.02x1023 units of a substance and is used to relate amounts of substances.
- Calculations involving moles and millimoles allow determining the amount of a substance in a sample based on its mass, molar mass, and the chemical formula. Factor-label and dimensional analysis
Presentation 2 chemistry , volumetric analysis A to ZTejNarayan15
1) The document discusses key concepts in chemistry including equivalent weight, volumetric analysis, titration, indicators, and methods of expressing concentration.
2) It provides examples of different types of titrations and selecting suitable indicators based on the pH curve for different acid-base reactions.
3) Formulas for normality, molarity and other concentration units are defined along with examples of calculating concentration from given values.
This document discusses different types of titrimetry including volumetric, coulometric, and gravimetric titrimetry. It describes key concepts in titrimetric analysis including standard solutions, equivalence points, end points, titration curves, and sources of error. Specific techniques are covered such as back titration, precipitation titrimetry using silver nitrate, and different types of indicators that can be used for argentometric (silver-based) titrations including chromate, fluorescein, and iron (III). Diagrams illustrate the titration process and how curves are affected by concentration and reaction completeness.
simple, sensitive, precise, accurate, highly reproducible and economical, visible spectrophotometric
method for the determination lurasidone in bulk form was developed and validated. The method is
based on the formation of an oxidative coupling product by the reaction of lurasidone with 3-methylbenzothiazolin-
2-one hydrazone as a chromogenic reagent in presence of ferric chloride. The linear regression
analysis data for the calibration plot showed good linear relationship within the concentration range of 0–
100 μg/mL with a correlation coefficient (r) value of 0.9997. The limits of detection and quantitation are 0.6
and 1.7 μg/mL, respectively. The method was tested and validated according to ICH guidelines. The results
demonstrated that the procedure is accurate, precise and reproducible (RSD < 2%).
Quantitative analysis and volumetric analysisMussaOmary3
This document provides information on quantitative analysis and volumetric analysis techniques. It defines key terms like concentration, molarity, and standard solutions. It describes common volumetric apparatus and how to perform acid-base titrations using appropriate indicators. It also covers concepts like molar ratios, dilution calculations, and determining water of crystallization through titration reactions. The document provides examples of calculations for molarity, concentration, purity, and molar mass determinations.
The document discusses chemical kinetics and reaction rates. It provides information on:
- The study of rates of chemical reactions and reaction mechanisms (chemical kinetics).
- How reaction rates are expressed in terms of changes in reactant/product concentrations over time.
- Factors that influence reaction rates such as concentration, temperature, and surface area.
- Collision theory and how effective collisions between reactant particles lead to reactions.
- Reaction orders, rate laws, and how to determine the order of reactions based on experimental rate data.
There is a global acceptance that out of the initial oil in place a maximum of about one third can be recovered by relying on depletion drive energy from the petroleum reservoir. To recover additional resources the depleted energy of the reservoir must be boosted. The usual approach involves water flooding and to maximize recovery under these conditions a sound knowledge of multiphase flow in porous media is required. Relative permeability is a fundamental multiphase flow function that has received immense attention in the petroleum industry. In this regard, a new model of water relative permeability based on resistivity measurement has been developed by Li (2004). He compared his relative permeability data to that obtained using the centrifuge. It was found to show close agreement.
This study was conducted with two primary objectives. The first was to compare the new model relative permeability to the widely used unsteady state relative permeability data using a Benchtop Relative Permeameter (BRP 350). The second was to investigate the sensitivity of the new model to brine salinity. The experiment was conducted at ambient conditions with different brine concentrations ranging from 2% to 10%. Results show that the new model predicts relative permeability similar to the Benchtop Relative Permeameter (BRP 350) at lower brine concentration (2%) and at higher brine concentration (4.5% and 10%) close agreement is perceived only at lower water saturations. In addition, the new model has been found not to be sensitive to salinity at lower brine concentration (2% NaCl – 4.5% NaCl) and found to be sensitive at higher brine concentration (10% NaCl).
This document summarizes a study on the spectroscopic and micellization properties of uranyl hexanoate in organic solvents. Infrared spectroscopy revealed that uranyl hexanoate has partial ionic character, with the fatty acids existing in a dimeric state through hydrogen bonding. Conductometric measurements determined the critical micellar concentration of uranyl hexanoate in DMF to be 0.03M. The addition of Sudan dye increased conductivity but did not change the critical micellar concentration. Uranyl hexanoate behaved as a simple electrolyte below the critical micellar concentration.
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1. International Journal of Engineering Research and General Science Volume 4, Issue 3, May-June, 2016
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DETERMINATION OF DENSITIES OF SOME R4NI- SOLUTION IN NMF-DMF
SOLVENT MIXTURES AT 250
C BY MAGNETIC FLOAT DENSITOMETER AND STUDY
MASSON’S EQUATION FROM ΦV-DATA
Indu Saxena1
, Rikkam Devi2
, Vijay Kumar3
, Sadhana Gautam4
1
Department of Chemistry, University of Lucknow, Lucknow U.P. (India) – 226007
E mail: indusaxena@cetglad.org
Phone no.: 9415344457
Abstract— A new technique of measuring the densities of solvents and solutions by using magnetic float densitometer has been given
.The densitometer works on the electrostatic attraction of force developed by the passage of current through a solenoid. Using this
technique, the densities (ρo‘s) of NMF-DMF mixtures at 0, 25, 50, 75, and 100% NMF in DMF (v/v) and those of solution (ρs
‘
s) of
some tetra alkyl ammonium iodide salts namely Et4NI, Pr4NI, Bu4NI and Pen4NI have been determined experimentally by magnetic
float densitometer at 25 0
C. The apparent molar volumes (ϕv) have been calculated from density data and a graph is plotted against √C.
The slopes, (Sv) of these curves show that in low dielectric constant (ϵ) medium all the four tetra alkyl ammonium salts have positive
slope. But as the dielectric constant (ϵ) of the solvent medium is increased by adding NMF in DMF, each of the four electrolytes has
negative slope. Such type of changes occurs due to the presence of specific molecular interactions between electrolyte ions and solvent
molecules which are responsible for the stability of molecular structure and causes change in the thermo-dynamical properties. It has
been explained on the basis of dielectric constant of the mixture, size and charge density of the electrolyte ion.
Keywords— Magnetic Float Densitometer, Apparent molar volume (ϕv), Dielectric constant (ϵ), N-methyl Formamide, Dimethyl
Formamide, Tetra alkyl ammonium iodide salts, molecular interactions.
INTRODUCTION
The study of apparent molar volumes (ϕv) [1, 9, 14, & 19]
of tetra alkyl ammonium salts R4NX in water and in non-aqueous solvent
mixtures, eg. Formamide, N-methyl Acetamide (NMA),N-methyl Propionamide (NMP), Dimethyl Sulphoxide (DMSO) and
Propylene Carbonate (PC) shows that the slope Sv of apparent molal volume, (ϕv) Vs √C varies with solvent to solvent and also show
positive as well as negative slope Sv – values for having low and high dielectric constant (ϵ) of the medium respectively. There are
various non- aqueous solvents with water as one of the constituent were also used by the scientists to prepare solutions of R4NX salts
as Aqueous-Non-aqueous mixtures and then verifying the Masson‘s equation by using apparent molar volume (ϕv) data. The dielectric
Constant of the medium was changed by adding, water to the non-aqueous solvent gradually.[13, 14]
The results of these workers
indicate that there seems to be an effect of dielectric of the combinations of two non- aqueous liquids giving the solvent mixtures of
varying dielectric constants using R4NI salts as solutes. But no one has carried out a systematic study covering entire range (lower to
higher) of dielectric constant (ϵ) of the medium. It seemed interesting for us to examine the problem of change of slope Sv, with
dielectric constant of the medium by selecting such combination of liquid which can cover the lowest to highest value dielectric
constant [11]
and also whose density values fit in according to our magnetic float densitometer [10]
requirement. This may perhaps throw
a light on the effect of dielectric constant (ϵ) on the variation of the slope, Sv – values. Such combination of liquid mixtures (DMSO-
Dioxane system) giving the lower to medium dielectric range [ϵ = 10.75 to 46.5] and the other combination, NMF- t-butanol Mixtures,
2. International Journal of Engineering Research and General Science Volume 4, Issue 3, May-June, 2016
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covering medium to high dielectric constant range [ϵ = 46.00 to 182.4] have already been studied. This Paper includes a system of two
liquids namely NMF-DMF mixtures, which suits us according to needs and requirement of our Magnetic Float Densitometer. This
system also covers medium to high dielectric constant range [ϵ = 36.7 to 182.40] of the liquid mixtures for our study. The Magnetic
Float Densitometer can be operated with those liquids or liquid mixtures whose density is greater than the density of the magnetic
float (that is it should be greater than 0.940010 g/ml).The density coverage of the selected system (NMF-DMF system) from 0% DMF
to 100% DMF is from 0.944000 to 1.011006 g/ml. In this paper R4NI salts (R= Et, Pr, Bu, Pen) are studied in NMF-DMF mixtures at
varying compositions from the point of view of apparent molar (Φv) using Magnetic Float Densitometer.
MATERIAL AND METHODS
Dimethyl Formamide (DMF), after drying on freshly ignited quicklime, was purified by repeated vacuum distillation. The specific
conductance of this sample was of the order of 10-7
mhos cm-1
. N-methyl Formamide [commercial grade, glaxo] was purified by
azeotropic distillation with benzene. There are four tetra alkyl ammonium iodide salts, Et4NI, Pr4NI, Bu4NI and Pen4NI, which were
used in the present investigation were purified by the method of Conway et al. Due to solubility restrictions Me4NI salt was excluded
from our present investigation. N-methy1 Formamide was gradually mixed with Di-methyl Formamide to get 0, 25, 50, 75 and 100%
NMF in DMF (v/v). The dielectric constants (ϵ) of these solvent mixtures were not found to be reported in the literature. Therefore
these were determined graphically by assuming the linear relationship between the dielectric constant (ϵ) and the composition. A
graph was plotted between dielectric constant and composition of solvent mixture .The values of dielectric constants of 0, 25, 50, 75,
and 100% NMF in DMF (v/v) mixtures, are computed from the graph. The values of dielectric constant (ϵ) are 36.7, 73.0, 109.5, 146.0
and 182.4 respectively.
Table 1: Estimated values of dielectric constants (ϵ) of the NMF+DMF Mixtures obtained from graph at 250
C
These solvent mixtures were used for making solutions of tetra alkyl ammonium salts. First of all the densities of 0, 25, 50, 75, and
100% NMF in DMF (v/v) mixtures were determined by Magnetic Float Densitometer at 250
C. For this, the solvent mixture was taken
in the solution container. The weights were added to the float so that it just touched the solution container. Then the current was
passed in the pull down solenoid and then in the main solenoid by operating the circuit in proper sequential steps, ie by selecting push
button no. 3 in top section; push button no. 2 in the battery section and then sequentially push button 1, 2 and 3 turn by turn in middle
section of circuit. The observations were taken for weight ‗w‘ and corresponding hold down current ‗I‘, when the float touch the
button of the solution container .For getting this equilibrium condition, the resistance bridge was also adjusted accordingly. Thus
different observations were taken for ‗w‘ and corresponding value ‗I‘ for each solvent mixture was recorded in a table 2. Then ρ value
Sr. No. Composition of NMF
in DMF (v/v)
Dielectric constant,
(ϵ)
1 0% NMF 36.7
2 25% NMF 73.0
3 50% NMF 109.5
4 75% NMF 146.0
5 100% NMF 182.4
3. International Journal of Engineering Research and General Science Volume 4, Issue 3, May-June, 2016
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was calculated at 250
C for each solvent mixture by using formula, ρ0 = (W + w + f × I) / (V + w/ρpt) [10].
Thus calculated ρ0‘s were
given in table 2.
Figure1: Graph plotted between dielectric constant (ϵ) and % compositions of NMF in DMF solvent.
Table 2: Estimated values of densities (ρ0‘s) of pure solvent mixtures at 250
C
RESULT AND DISCUSSION
The curves from Figure.2 of apparent molar volume ϕv v/s √C for Et4NI, Pr4NI, Bu4NI and Pen4NI electrolytes are straight lines for the
entire concentration range (0.002M – 0.026M) studied. Therefore Masson‘s equation ϕv = ϕv◦ + Sv √C [2, 3 12]
is valid for these
electrolytes in DMF - NMF solvent mixtures also. Fig. 2 shows that ϕv v/s √C curves have positive slope in 0% NMF in DMF (i.e. in
pure DMF) for all the above four electrolytes. The apparent molar volume (ϕv) increases with increase in electrolytes concentration
and the density of Solutions also increases in each case as is evident from tables 3 to 6. Though the slope of each curve is positive yet
it gradually decreases from Et4NI to Pen4NI. The value of apparent molar volume (ϕv) is greater for a molecule of larger size than the
0 20 40 60 80 100
0
20
40
60
80
100
120
140
160
180
200
dielectricconstant()
% Composition of NMF in DMF solution
Sr. No. % Composition (v/v)
of NMF in DMF
W
(g)
I
(mA)
ρ0
(g/ml)
1. 0% NMF 0.200 83.5 0.944000
2. 25% NMF 1.600 106.8 0.960700
3. 50% NMF 2.800 255 0.977549
4. 75% NMF 4.600 36.3 0.994000
5. 100% NMF 6.000 79.0 1.011006
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preceding one at a definite concentration. [4, 5, 6, 7, 8]
The slope Sv becomes negative as we mix 25 % NMF in DMF (ρ0 = 0.960700, ϵ =
73.0), that is, if dielectric constant (ϵ) of the medium is increased from ϵ = 36.7 to ϵ =73.0 by adding N-Methyl Formamide.
Table 3: Estimated values of weight (w), used, current (I), passing in the circuit and the corresponding values of ɸV
For 75% NMF in DMF Et4NI salt solution at 250
C
Table 4: Estimated values of weight (w), used, current (I), passing in the circuit and the corresponding values of ɸV
For 75% NMF in DMF Pr4NI salt solution at 250
C
Sr.
No.
M
(molarity)
w
(g)
I
(mA)
ρ
(g ml-1
)
√C
mole1/2
dm-3/2
ɸV
dm3
.mole-1
×103
1. 0.002 4.610 39.5 0.994179 0.045 225.12
2. 0.006 4.620 54.0 0.994584 0.08 217.24
3. 0.010 4.630 70.0 0.995018 0.10 212.75
4. 0.014 4.640 87.0 0.995472 0.12 209.38
5. 0.018 4.650 102.5 0.995896 0.13 209.19
6. 0.022 4.660 122.5 0.996409 0.15 205.00
7. 0.026 4.670 140.0 0.996873 0.16 203.99
Table 5: Estimated values of weight (w), used, current (I), passing in the circuit and the corresponding values of ɸV
For 75% NMF in DMF Bu4NI salt solution at 250
C
Sr.
No.
M
(molarity)
w
(g)
I
(mA)
ρ
(g ml-1
)
√C
mole1/2
dm-3/2
ɸV
dm3
.mole-1
×103
1. 0.002 4.610 39.0 0.994169 0.045 286.60
2. 0.006 4.620 53.0 0.994564 0.08 277.04
Sr.
No.
M
(molarity)
w
(g)
I
(mA)
ρ
(g ml-1
)
√C
mole1/2
dm-3/2
ɸV
dm3
.mole-1
×103
1. 0.002 4.610 40.5 0.994199 0.045 158.61
2. 0.006 4.620 57.0 0.994643 0.08 150.90
3. 0.010 4.630 74.0 0.995097 0.10 148.35
4. 0.014 4.640 92.0 0.995571 0.12 145.82
5. 0.018 4.650 110.0 0.996045 0.13 144.42
6. 0.022 4.660 130.0 0.996559 0.15 141.69
7. 0.026 4.670 147.5 0.997022 0.16 141.78
5. International Journal of Engineering Research and General Science Volume 4, Issue 3, May-June, 2016
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3. 0.010 4.630 68.5 0.994988 0.10 272.21
4. 0.014 4.640 85.5 0.995442 0.12 267.99
5. 0.018 4.650 102.5 0.995896 0.13 265.64
6. 0.022 4.660 122.5 0.996409 0.15 261.45
7. 0.026 4.670 140.0 0.996873 0.16 260.44
Table 6: Estimated values of weight (w), used, current (I), passing in the circuit and the corresponding values of ɸV
For 75% NMF in DMF Pen4NI salt solution at 250
C
Sr.
No.
M
(molarity)
w
(g)
I
(mA)
ρ
(g ml-1
)
√C
mole1/2
dm-3/2
ɸV
dm3
.mole-1
×103
1. 0.002 4.610 39.5 0.994179 0.045 338.02
2. 0.006 4.620 54.0 0.994584 0.08 330.14
3. 0.010 4.630 70.0 0.995018 0.10 325.64
4. 0.014 4.640 88.5 0.995501 0.12 320.20
5. 0.018 4.650 105.5 0.995945 0.13 319.35
6. 0.022 4.660 127.5 0.996509 0.15 313.32
7. 0.026 4.670 150.0 0.997072 0.16 309.19
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Figure 2: Graph plotted between apparent molar volume (ϕv) and root of concentration (C1/2
) of binary salt solutions
(NMF + DMF + Salt).
The slope of all the electrolytes remains negatives in next other three compositions of NMF and DMF i.e. in 50, 75 and 100 % NMF.
The electrolytes have positive slope in fig. 20 but these electrolytes have negative slope in fig. 21. As we proceed from fig. 21 to 24,
the negative value of slope goes on increasing ie, the lines become more and more steep. Each figure shows that the steepness is
higher for Pen4NI than for Bu4NI and, in turn, it is higher for Bu4NI than Pr4NI and so on. Thus it increases Et4NI to Pen4NI in the
order Et4NI < Pr4NI < Bu4NI < Pen4NI in a given solvent mixture having compositions 25% and more. In other wards if we look at the
fig. 20 to 24 and see the nature of variation of slope from Et4 NI to Pen4NI in each solvent mixture (0, 25, 50, 75, and 100%, NMF in
DMF). It decreases from smaller tetra alkyl ammonium ion to larger tetra alkyl ammonium ion, (ie. The negative slope becomes more
negative). Table LXXII clearly show that for each electrolyte, the slope goes on decreasing as the dielectric constant is increased, by
adding NMF gradually to DMF. It also decreases from Et4NI TO Pen4NI for a definite composition of solvent mixture. The
observations of fig. 20 and 21 reveal that the changeover of the slope from positive to negative takes place at somewhere between 0%
and 25% NMF, that is, between the dielectric constant ϵ = 36.7 and 73.0.
ACKNOWLEDGMENT
The author thanks to the head of the Chemistry Department, Lucknow University for providing the research facility in the Department.
CONCLUSION
The apparent molar volumes (ϕv) are positive and large for all the tetraalkyl ammonium salts in all the % compositions of NMF in
DMF solvent due to the presence of weak ionic interactions of the solvent molecule. Thus we conclude that the variation of slope Sv –
value from Et4NI (smaller in size) to Pen4NI (larger in size) shown in table no. 7. Table.7 clearly indicates that the Sv – value goes on
decreasing as the dielectric constant (ϵ) is increased for each electrolyte, by adding NMF to DMF gradually to a definite %
composition of solvent mixture. This observation confermed that the changeover of the slope from positive to negative takes place at
somewhere between 0 % and 25 % NMF (ϵ =36.7 to 73.0)
0.04 0.06 0.08 0.10 0.12 0.14 0.16
140
160
180
200
220
240
260
280
300
320
340
dm
3
.mole
-1
×10
3
C
1/2
mole
1/2
dm
-3/2
Et4
NI
Pr4
NI
Bu4
NI
Pen4
NI
7. International Journal of Engineering Research and General Science Volume 4, Issue 3, May-June, 2016
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REFERENCES:
[1] Pathak R N, Saxena I, Archana and Mishra A K, (2009) ―Study of the Influence of Alkyl Chain Cation Solvent
Interactions on the Slope of ФV vs. √C Curves in 1,5-Pentane Diol - DMF Solvent Mixtures by Apparent Molar Volume
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