The document discusses various topics related to solutions and electrochemistry. It begins by defining solutions and different ways of expressing concentration such as molarity, molality and normality. It then discusses solutions of gases in gases based on Henry's law and solutions of liquids in liquids, including completely miscible and partially miscible liquids. Other topics covered include solubility, vapor pressure of solutions, distillation, and colligative properties of solutions such as boiling point elevation, freezing point depression, and vapor pressure lowering. Measurement techniques for various colligative properties are also summarized.
This document discusses electrolytic solutions and electrochemistry. It begins by defining electrochemistry as the study of chemical reactions involving electron transfer between an electrode and electrolyte. It then discusses different types of solutions, distinguishing between electrolytic and non-electrolytic solutions. Electrolytic solutions contain ions and are electrically conductive. The document also discusses the differences between electronic and electrolytic conductors, and how conductivity is affected by various factors like temperature, concentration, and ion size. It introduces concepts like equivalent conductance, molar conductance, activity, and activity coefficients. In summary, the document provides an overview of key concepts relating to electrolytic solutions and electrochemistry.
This presentation consists of three topics that are:
1. conductance of electrolytic solution
2. Specific Conductance, Molar Conductance & Equivalent Conductance
3. Kohlrausch's Law
This document discusses the properties and importance of water and non-aqueous solvents. It notes that while water is a common solvent, it has limitations for reactions involving strong acids/bases or reducing agents. Non-aqueous solvents allow these types of reactions and can change product outcomes. Important properties of solvents discussed include melting/boiling points, heat of fusion/vaporization, dielectric constant, dipole moment, and viscosity - all of which influence a solvent's ability to dissolve different types of compounds. Non-aqueous solvents like liquid ammonia and sulfur dioxide expand the scope of chemical reactions.
Electrode potential and its applicationsSaba Shahzadi
This document provides an overview of electrode potential and electrochemistry. It defines electrode potential as the voltage at an electrode that must be measured versus a reference electrode. Electrochemistry involves the interconversion of electrical and chemical energy through electrochemical cells, which contain two electrodes where oxidation and reduction reactions occur. The potential difference between the electrodes is known as the electromotive force (EMF) or cell potential. Electrode potential can be used to determine various properties including the strengths of oxidizing/reducing agents, thermodynamic potentials, concentrations, and equilibrium constants.
This document discusses applications of cyclic voltammetry (CV). CV is an electrochemical technique useful for studying electrode reactions. It involves applying a continuous, cyclic potential to a working electrode in a cell containing three electrodes. The document outlines the principle, working, and applications of CV, including quantitative analysis, studying chemical reactivity and redox processes, determining thermodynamic properties, kinetics, and more. Examples are given of using CV to characterize modified electrodes and study interactions like of anticancer drugs with DNA.
1. Electrochemistry deals with the transformation of electrical energy to chemical energy and vice versa. It involves the chemical applications of electricity.
2. An electrolytic cell converts electrical energy to chemical energy, while an electrochemical cell converts chemical energy to electrical energy.
3. Arrhenius' theory of electrolytic dissociation states that when an electrolyte dissolves in water, it breaks up into ions. There is a dynamic equilibrium between the ionized and non-ionized molecules. The degree of ionization depends on factors like the ionization constant.
This document provides an overview of chemical kinetics and reaction rates. It discusses:
1) Chemical kinetics deals with how fast chemical reactions occur and the factors that affect reaction rates.
2) Reaction rates can vary significantly, from fractions of a second to years, as seen in examples of iron rusting and silver chloride formation.
3) The study of chemical kinetics involves determining rates of reaction, factors affecting rates, and reaction mechanisms.
It then provides examples and methods for determining reaction order and the effect of temperature on reaction rates.
This document provides information about oxidation-reduction (redox) reactions and electrochemical cells. It discusses how redox reactions can be separated into half-reactions that occur at different electrodes. As an example, it examines the redox reaction between copper and silver ions and how this reaction spontaneously occurs when the metals are placed in their respective ion solutions, but not in the reverse direction. It also explains how electrochemical cells like galvanic cells and electrolytic cells use separated half-reactions to generate a voltage or cause non-spontaneous reactions, respectively. Key concepts covered include the standard hydrogen electrode, conventions for assigning electrode potentials, and how voltages relate to the thermodynamics of redox processes.
This document discusses electrolytic solutions and electrochemistry. It begins by defining electrochemistry as the study of chemical reactions involving electron transfer between an electrode and electrolyte. It then discusses different types of solutions, distinguishing between electrolytic and non-electrolytic solutions. Electrolytic solutions contain ions and are electrically conductive. The document also discusses the differences between electronic and electrolytic conductors, and how conductivity is affected by various factors like temperature, concentration, and ion size. It introduces concepts like equivalent conductance, molar conductance, activity, and activity coefficients. In summary, the document provides an overview of key concepts relating to electrolytic solutions and electrochemistry.
This presentation consists of three topics that are:
1. conductance of electrolytic solution
2. Specific Conductance, Molar Conductance & Equivalent Conductance
3. Kohlrausch's Law
This document discusses the properties and importance of water and non-aqueous solvents. It notes that while water is a common solvent, it has limitations for reactions involving strong acids/bases or reducing agents. Non-aqueous solvents allow these types of reactions and can change product outcomes. Important properties of solvents discussed include melting/boiling points, heat of fusion/vaporization, dielectric constant, dipole moment, and viscosity - all of which influence a solvent's ability to dissolve different types of compounds. Non-aqueous solvents like liquid ammonia and sulfur dioxide expand the scope of chemical reactions.
Electrode potential and its applicationsSaba Shahzadi
This document provides an overview of electrode potential and electrochemistry. It defines electrode potential as the voltage at an electrode that must be measured versus a reference electrode. Electrochemistry involves the interconversion of electrical and chemical energy through electrochemical cells, which contain two electrodes where oxidation and reduction reactions occur. The potential difference between the electrodes is known as the electromotive force (EMF) or cell potential. Electrode potential can be used to determine various properties including the strengths of oxidizing/reducing agents, thermodynamic potentials, concentrations, and equilibrium constants.
This document discusses applications of cyclic voltammetry (CV). CV is an electrochemical technique useful for studying electrode reactions. It involves applying a continuous, cyclic potential to a working electrode in a cell containing three electrodes. The document outlines the principle, working, and applications of CV, including quantitative analysis, studying chemical reactivity and redox processes, determining thermodynamic properties, kinetics, and more. Examples are given of using CV to characterize modified electrodes and study interactions like of anticancer drugs with DNA.
1. Electrochemistry deals with the transformation of electrical energy to chemical energy and vice versa. It involves the chemical applications of electricity.
2. An electrolytic cell converts electrical energy to chemical energy, while an electrochemical cell converts chemical energy to electrical energy.
3. Arrhenius' theory of electrolytic dissociation states that when an electrolyte dissolves in water, it breaks up into ions. There is a dynamic equilibrium between the ionized and non-ionized molecules. The degree of ionization depends on factors like the ionization constant.
This document provides an overview of chemical kinetics and reaction rates. It discusses:
1) Chemical kinetics deals with how fast chemical reactions occur and the factors that affect reaction rates.
2) Reaction rates can vary significantly, from fractions of a second to years, as seen in examples of iron rusting and silver chloride formation.
3) The study of chemical kinetics involves determining rates of reaction, factors affecting rates, and reaction mechanisms.
It then provides examples and methods for determining reaction order and the effect of temperature on reaction rates.
This document provides information about oxidation-reduction (redox) reactions and electrochemical cells. It discusses how redox reactions can be separated into half-reactions that occur at different electrodes. As an example, it examines the redox reaction between copper and silver ions and how this reaction spontaneously occurs when the metals are placed in their respective ion solutions, but not in the reverse direction. It also explains how electrochemical cells like galvanic cells and electrolytic cells use separated half-reactions to generate a voltage or cause non-spontaneous reactions, respectively. Key concepts covered include the standard hydrogen electrode, conventions for assigning electrode potentials, and how voltages relate to the thermodynamics of redox processes.
Class XII Electrochemistry - Nernst equation.Arunesh Gupta
This document provides an overview of electrochemistry and some key concepts. It begins by defining electrochemistry as the study of how spontaneous chemical reactions can produce electricity and how electrical energy can drive non-spontaneous reactions. It then discusses several applications of electrochemistry including metal production, electroplating, and batteries. The document goes on to define conductors and the differences between metallic and electrolytic conduction. It also introduces concepts like galvanic cells, salt bridges, standard electrode potentials, and the electrochemical series. In summary, the document provides a broad introduction to fundamental electrochemistry topics and concepts.
Voltammetry is a technique where a time-dependent potential is applied to an electrochemical cell and the current is measured as a function of the applied potential. This results in a voltammogram which provides qualitative and quantitative information about redox reactions. The earliest technique was polarography developed in the 1920s. Modern voltammetry uses a three-electrode system with various excitation signals applied. Common techniques include normal pulse polarography, differential pulse polarography, staircase polarography and square wave polarography which have better sensitivity than normal polarography. The shape of the voltammetric wave depends on factors like the reversibility of the redox reaction. The diffusion current occurs at very negative potentials where the reaction rate is controlled by diffusion
Polarography is an electroanalytical technique invented by Jaroslav Heyrovsky in 1922. It involves using a dropping mercury electrode and measuring the current in the solution at different applied potentials to generate a current-voltage curve called a polarogram. There are four main types of current measured: residual, migration, diffusion, and limiting current. The construction includes a dropping mercury electrode, supporting electrolyte, mercury reservoir, and capillary tube. Polarography can be used for qualitative and quantitative analysis of samples without separation and allows analysis of small amounts of inorganic and organic substances.
Shielding effect,effect of chemical exchange,hydrogen bondingSumeetJha12
This document summarizes key concepts related to NMR spectroscopy, including shielding effect, hydrogen bonding, and chemical exchange. It describes how the shielding effect causes some nuclei to experience less of an external magnetic field, requiring a higher frequency for resonance. Hydrogen bonding causes deshielding and higher chemical shift values as electron density around protons decreases. Chemical exchange refers to nuclei switching environments, which can lead to sharp, broad, or coupled peaks depending on the exchange rate relative to peak separation.
Electron spin resonance (ESR) spectroscopy is a technique used to study compounds with unpaired electrons. In ESR, a sample is placed in a static magnetic field and irradiated with microwaves. This causes transitions between the electron spin energy levels. The absorption of microwave energy is detected to obtain an ESR spectrum. ESR spectra provide information about electron environments through parameters like g-values and hyperfine splitting patterns. ESR finds applications in studying transition metal complexes and unstable free radicals.
The document discusses the lability and inertness of coordination complexes. It defines labile complexes as those where ligand exchange occurs rapidly, while inert complexes have slow ligand exchange. Lability is determined by factors like the metal ion size, charge, and d-electron configuration, not thermodynamic stability. Smaller or higher charged metal ions and complexes with less than 3 d-electrons tend to be more labile. The rate of ligand substitution depends on both the leaving and entering ligands. Steric effects and solvent also influence the rate. Complexes may undergo dissociative or associative substitution based on their structure.
This document discusses various concepts related to gravimetric analysis methods. It covers three key points:
1) Gravimetric analysis involves selectively precipitating the analyte of interest and weighing the precipitate to determine the amount of analyte. Factors like solubility products (Ksp), common ion effects, and pH can impact precipitation.
2) Key steps in gravimetric analysis are discussed, including filtering, drying, and transferring precipitates. Equipment like filters, crucibles, and drying ovens are also mentioned.
3) Solubility is impacted by various equilibrium concepts like Ksp values, common ion effects, salt effects, pH, complexation, and temperature. These concepts are illustrated through
This document discusses different types of electrodes used in electroanalytical chemistry. It describes inert electrodes like platinum, gold and graphite that do not participate in reactions, and reactive electrodes like zinc, copper and lead that actively participate in reactions. The document discusses various types of electrodes in detail, including glass electrodes, liquid ion exchanger membranes, solid state membranes, neutral carrier membranes, coated wire electrodes, and ion selective field effect transistors. It also outlines the principle, advantages, limitations and applications of ion selective electrodes.
Electrochemistry is the study of chemical reactions caused by the passage of an electric current and the production of electrical energy from chemical reactions. It encompasses phenomena like corrosion and devices like batteries and fuel cells. Electrochemical cells are either electrolytic cells, where an external power source drives non-spontaneous reactions, or galvanic/voltaic cells, where spontaneous reactions produce electricity. The kinetics and rates of electrochemical reactions, as well as mass transfer of reactants, influence current production in fuel cells and other devices.
Coulometry is an electroanalytical technique where the amount of electricity (in coulombs) required to complete an electrochemical reaction is measured. There are two main types - potentiostatic coulometry, where the potential is held constant, and coulometric titration with a constant current. The quantity of electricity is directly proportional to the amount of analyte and can be used to determine concentrations. Coulometry has applications in inorganic analysis, analysis of radioactive materials, microanalysis, and determination of organic compounds.
Electrogravimetric analysis involves the quantitative deposition of an analyte onto an electrode through electrolysis. There are two main types: constant current electrolysis, where the current is kept constant and the potential varies, and controlled potential electrolysis, where the potential is kept constant to selectively deposit analytes. Electrogravimetric analysis can be used for quantitative analysis, separation, preconcentration of analytes, and electrosynthesis.
Colligative properties such as boiling point elevation, freezing point depression, and osmotic pressure depend only on the number of solute particles in solution, not their identity. The document discusses these properties and how they are affected when solutes dissolve. It explains that boiling point is elevated and freezing point is depressed because solutes lower vapor pressure, requiring more energy for phase changes. Osmotic pressure arises from differences in solute concentration across a semipermeable membrane. The van't Hoff factor accounts for changes in observed properties when solutes dissociate or associate in solution.
The document discusses kinetics and reaction rates. It defines kinetics as the branch of chemistry that studies the speed or rate of chemical reactions. It explains that reaction rates can be measured by changes in concentration, temperature, or pressure over time. The rate depends on factors like the nature of reactants, concentration, temperature, catalysts, surface area, and pressure. Reactions may occur in multiple steps through reaction intermediates rather than a single step. The collision theory and concept of activation energy are introduced to explain why certain collisions result in reactions. Reaction coordinate diagrams are used to illustrate the energy changes in reactions.
Theory of Acid-base Indicators and Acid-base Titration CurvesSajjad Ullah
1) Acid-base indicators change color at a specific pH range near the equivalence point of an acid-base titration. This allows the endpoint to be visually identified.
2) The pH curve for a strong acid-strong base titration shows a sharp change in pH at the equivalence point of 7. A weak acid-strong base titration has a more gradual pH change before and after the equivalence point, which is above 7 due to salt hydrolysis.
3) The suitable indicator depends on the pH changes around the endpoint. It must change color in the steep "vertical" portion of the curve to accurately identify the endpoint.
Coulometry is an electroanalytical technique that measures the quantity of electricity required for a chemical reaction. There are two main types - controlled potential coulometry (potentiostatic coulometry) and controlled current coulometry (galvanostatic coulometry). Controlled potential coulometry involves holding the working electrode at a constant potential to allow exhaustive electrolysis of the analyte without interfering reactions. The quantity of electricity passed is proportional to the analyte concentration and is measured with an electronic integrator. Applications include determination of metal ions, microanalysis, and analysis of radioactive materials like uranium.
These slides briefly introduce the concepts of Radio-chemistry including nuclear stability, half life, nuclear emissions and their detection, and then highlight 02 radio chemical methods namely isotopic dilution methods and radio-chemical titrations.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds or substance . The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds........
This document discusses reference electrodes, which maintain a constant potential regardless of current. It describes how reference electrodes establish a reference point for measuring potential in voltammetric methods. An ideal reference electrode uses stable, well-defined half-cell components. The standard hydrogen electrode (SHE) is described as the reference, but it is impractical, so saturated calomel electrodes (SCE) and silver/silver chloride electrodes are commonly used instead as they offer stable, reproducible potentials. The SCE consists of mercury coated with mercurous chloride paste and immersed in saturated potassium chloride solution, while the Ag/AgCl electrode uses silver wire coated with solid silver chloride in saturated potassium chloride solution.
Volumetric Analysis ( Titrimetric analysis) or TitrationAman Kakne
Volumetric analysis, also known as titrimetric analysis, is a quantitative analysis technique that determines the concentration of an unknown substance by titrating it with a solution of known concentration. The key steps are: (1) adding a known volume of the titrant of known concentration to the titrate of unknown concentration until the endpoint is reached, as indicated by a pH indicator; (2) recording the titrant volume used; and (3) calculating the concentration of the titrate based on the reaction stoichiometry and volumes added. Common types of titrations include acid-base titrations, redox titrations, and precipitation titrations. Proper indicator selection based on the relative acid/base strengths is
1. The document discusses solutions of non-electrolytes, including concentration terms like molarity, molality, and mole fraction. It also discusses ideal and non-ideal solutions, and how they obey or deviate from Raoult's law.
2. Partial miscible liquids are discussed, including phenol-water, trimethylamine-water, and nicotine-water systems. These can have upper, lower, or both upper and lower critical solution temperatures.
3. Azeotropes are briefly covered, including maximum and minimum boiling mixtures like ethanol-water. Fractional distillation and steam distillation are also mentioned for separating azeotropic mixtures.
1. A solution is a homogeneous mixture of one or more solutes dissolved in a solvent. Solubility refers to the ability of a solute to dissolve in a solvent.
2. Henry's law states that the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of the gas above the liquid at a constant temperature.
3. Colligative properties depend on the number of solute particles in solution, not their identity, and include vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.
Class XII Electrochemistry - Nernst equation.Arunesh Gupta
This document provides an overview of electrochemistry and some key concepts. It begins by defining electrochemistry as the study of how spontaneous chemical reactions can produce electricity and how electrical energy can drive non-spontaneous reactions. It then discusses several applications of electrochemistry including metal production, electroplating, and batteries. The document goes on to define conductors and the differences between metallic and electrolytic conduction. It also introduces concepts like galvanic cells, salt bridges, standard electrode potentials, and the electrochemical series. In summary, the document provides a broad introduction to fundamental electrochemistry topics and concepts.
Voltammetry is a technique where a time-dependent potential is applied to an electrochemical cell and the current is measured as a function of the applied potential. This results in a voltammogram which provides qualitative and quantitative information about redox reactions. The earliest technique was polarography developed in the 1920s. Modern voltammetry uses a three-electrode system with various excitation signals applied. Common techniques include normal pulse polarography, differential pulse polarography, staircase polarography and square wave polarography which have better sensitivity than normal polarography. The shape of the voltammetric wave depends on factors like the reversibility of the redox reaction. The diffusion current occurs at very negative potentials where the reaction rate is controlled by diffusion
Polarography is an electroanalytical technique invented by Jaroslav Heyrovsky in 1922. It involves using a dropping mercury electrode and measuring the current in the solution at different applied potentials to generate a current-voltage curve called a polarogram. There are four main types of current measured: residual, migration, diffusion, and limiting current. The construction includes a dropping mercury electrode, supporting electrolyte, mercury reservoir, and capillary tube. Polarography can be used for qualitative and quantitative analysis of samples without separation and allows analysis of small amounts of inorganic and organic substances.
Shielding effect,effect of chemical exchange,hydrogen bondingSumeetJha12
This document summarizes key concepts related to NMR spectroscopy, including shielding effect, hydrogen bonding, and chemical exchange. It describes how the shielding effect causes some nuclei to experience less of an external magnetic field, requiring a higher frequency for resonance. Hydrogen bonding causes deshielding and higher chemical shift values as electron density around protons decreases. Chemical exchange refers to nuclei switching environments, which can lead to sharp, broad, or coupled peaks depending on the exchange rate relative to peak separation.
Electron spin resonance (ESR) spectroscopy is a technique used to study compounds with unpaired electrons. In ESR, a sample is placed in a static magnetic field and irradiated with microwaves. This causes transitions between the electron spin energy levels. The absorption of microwave energy is detected to obtain an ESR spectrum. ESR spectra provide information about electron environments through parameters like g-values and hyperfine splitting patterns. ESR finds applications in studying transition metal complexes and unstable free radicals.
The document discusses the lability and inertness of coordination complexes. It defines labile complexes as those where ligand exchange occurs rapidly, while inert complexes have slow ligand exchange. Lability is determined by factors like the metal ion size, charge, and d-electron configuration, not thermodynamic stability. Smaller or higher charged metal ions and complexes with less than 3 d-electrons tend to be more labile. The rate of ligand substitution depends on both the leaving and entering ligands. Steric effects and solvent also influence the rate. Complexes may undergo dissociative or associative substitution based on their structure.
This document discusses various concepts related to gravimetric analysis methods. It covers three key points:
1) Gravimetric analysis involves selectively precipitating the analyte of interest and weighing the precipitate to determine the amount of analyte. Factors like solubility products (Ksp), common ion effects, and pH can impact precipitation.
2) Key steps in gravimetric analysis are discussed, including filtering, drying, and transferring precipitates. Equipment like filters, crucibles, and drying ovens are also mentioned.
3) Solubility is impacted by various equilibrium concepts like Ksp values, common ion effects, salt effects, pH, complexation, and temperature. These concepts are illustrated through
This document discusses different types of electrodes used in electroanalytical chemistry. It describes inert electrodes like platinum, gold and graphite that do not participate in reactions, and reactive electrodes like zinc, copper and lead that actively participate in reactions. The document discusses various types of electrodes in detail, including glass electrodes, liquid ion exchanger membranes, solid state membranes, neutral carrier membranes, coated wire electrodes, and ion selective field effect transistors. It also outlines the principle, advantages, limitations and applications of ion selective electrodes.
Electrochemistry is the study of chemical reactions caused by the passage of an electric current and the production of electrical energy from chemical reactions. It encompasses phenomena like corrosion and devices like batteries and fuel cells. Electrochemical cells are either electrolytic cells, where an external power source drives non-spontaneous reactions, or galvanic/voltaic cells, where spontaneous reactions produce electricity. The kinetics and rates of electrochemical reactions, as well as mass transfer of reactants, influence current production in fuel cells and other devices.
Coulometry is an electroanalytical technique where the amount of electricity (in coulombs) required to complete an electrochemical reaction is measured. There are two main types - potentiostatic coulometry, where the potential is held constant, and coulometric titration with a constant current. The quantity of electricity is directly proportional to the amount of analyte and can be used to determine concentrations. Coulometry has applications in inorganic analysis, analysis of radioactive materials, microanalysis, and determination of organic compounds.
Electrogravimetric analysis involves the quantitative deposition of an analyte onto an electrode through electrolysis. There are two main types: constant current electrolysis, where the current is kept constant and the potential varies, and controlled potential electrolysis, where the potential is kept constant to selectively deposit analytes. Electrogravimetric analysis can be used for quantitative analysis, separation, preconcentration of analytes, and electrosynthesis.
Colligative properties such as boiling point elevation, freezing point depression, and osmotic pressure depend only on the number of solute particles in solution, not their identity. The document discusses these properties and how they are affected when solutes dissolve. It explains that boiling point is elevated and freezing point is depressed because solutes lower vapor pressure, requiring more energy for phase changes. Osmotic pressure arises from differences in solute concentration across a semipermeable membrane. The van't Hoff factor accounts for changes in observed properties when solutes dissociate or associate in solution.
The document discusses kinetics and reaction rates. It defines kinetics as the branch of chemistry that studies the speed or rate of chemical reactions. It explains that reaction rates can be measured by changes in concentration, temperature, or pressure over time. The rate depends on factors like the nature of reactants, concentration, temperature, catalysts, surface area, and pressure. Reactions may occur in multiple steps through reaction intermediates rather than a single step. The collision theory and concept of activation energy are introduced to explain why certain collisions result in reactions. Reaction coordinate diagrams are used to illustrate the energy changes in reactions.
Theory of Acid-base Indicators and Acid-base Titration CurvesSajjad Ullah
1) Acid-base indicators change color at a specific pH range near the equivalence point of an acid-base titration. This allows the endpoint to be visually identified.
2) The pH curve for a strong acid-strong base titration shows a sharp change in pH at the equivalence point of 7. A weak acid-strong base titration has a more gradual pH change before and after the equivalence point, which is above 7 due to salt hydrolysis.
3) The suitable indicator depends on the pH changes around the endpoint. It must change color in the steep "vertical" portion of the curve to accurately identify the endpoint.
Coulometry is an electroanalytical technique that measures the quantity of electricity required for a chemical reaction. There are two main types - controlled potential coulometry (potentiostatic coulometry) and controlled current coulometry (galvanostatic coulometry). Controlled potential coulometry involves holding the working electrode at a constant potential to allow exhaustive electrolysis of the analyte without interfering reactions. The quantity of electricity passed is proportional to the analyte concentration and is measured with an electronic integrator. Applications include determination of metal ions, microanalysis, and analysis of radioactive materials like uranium.
These slides briefly introduce the concepts of Radio-chemistry including nuclear stability, half life, nuclear emissions and their detection, and then highlight 02 radio chemical methods namely isotopic dilution methods and radio-chemical titrations.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds or substance . The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds........
This document discusses reference electrodes, which maintain a constant potential regardless of current. It describes how reference electrodes establish a reference point for measuring potential in voltammetric methods. An ideal reference electrode uses stable, well-defined half-cell components. The standard hydrogen electrode (SHE) is described as the reference, but it is impractical, so saturated calomel electrodes (SCE) and silver/silver chloride electrodes are commonly used instead as they offer stable, reproducible potentials. The SCE consists of mercury coated with mercurous chloride paste and immersed in saturated potassium chloride solution, while the Ag/AgCl electrode uses silver wire coated with solid silver chloride in saturated potassium chloride solution.
Volumetric Analysis ( Titrimetric analysis) or TitrationAman Kakne
Volumetric analysis, also known as titrimetric analysis, is a quantitative analysis technique that determines the concentration of an unknown substance by titrating it with a solution of known concentration. The key steps are: (1) adding a known volume of the titrant of known concentration to the titrate of unknown concentration until the endpoint is reached, as indicated by a pH indicator; (2) recording the titrant volume used; and (3) calculating the concentration of the titrate based on the reaction stoichiometry and volumes added. Common types of titrations include acid-base titrations, redox titrations, and precipitation titrations. Proper indicator selection based on the relative acid/base strengths is
1. The document discusses solutions of non-electrolytes, including concentration terms like molarity, molality, and mole fraction. It also discusses ideal and non-ideal solutions, and how they obey or deviate from Raoult's law.
2. Partial miscible liquids are discussed, including phenol-water, trimethylamine-water, and nicotine-water systems. These can have upper, lower, or both upper and lower critical solution temperatures.
3. Azeotropes are briefly covered, including maximum and minimum boiling mixtures like ethanol-water. Fractional distillation and steam distillation are also mentioned for separating azeotropic mixtures.
1. A solution is a homogeneous mixture of one or more solutes dissolved in a solvent. Solubility refers to the ability of a solute to dissolve in a solvent.
2. Henry's law states that the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of the gas above the liquid at a constant temperature.
3. Colligative properties depend on the number of solute particles in solution, not their identity, and include vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.
The document discusses various properties of liquids including intermolecular forces, vapor pressure, boiling point, surface tension, viscosity, refractive index, and optical activity. It describes three main types of intermolecular forces that exist in liquids: dipole-dipole interactions, London forces, and hydrogen bonding. Vapor pressure is defined as the pressure exerted by a liquid's vapor when in equilibrium, and it increases with temperature, affecting the boiling point. Methods for measuring properties like surface tension, viscosity, refractive index, and optical activity are also outlined.
This document provides information on solutions, including different types of solutions classified based on the phase of the solvent and solute. It discusses liquid solutions in detail and different methods of expressing the concentration of solutions such as molarity, molality, and normality.
It describes factors that affect solubility such as nature of solute and solvent, temperature, and pressure. The document explains concepts like saturated solutions, unsaturated solutions, and solubility curves. It introduces Henry's law which states that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas.
The document also discusses Raoult's law, ideal and non-ideal solutions, and deviations from Raoult's
This solution exhibits nonideal behavior. Acetone and chloroform are both volatile liquids that contribute to the total vapor pressure. To determine if it is ideal or nonideal, we would need the individual vapor pressures of acetone and chloroform at 35°C and their mole fractions in order to use the modified Raoult's law equation and compare the calculated total pressure to the measured 260 torr.
This document discusses the importance and definitions of solubility in pharmaceutical science. It defines key terms like solution, solute, solvent, saturated solution, and discusses the quantitative and qualitative ways of describing solubility. The document outlines factors that influence drug solubility like temperature, nature of solvent, pH, and particle size. It also discusses concepts like thermodynamic solubility, solubility expressions, solute-solvent interactions, and laws governing solubility like Raoult's law, ideal and non-ideal solutions, and distribution law.
The document discusses key concepts about solutions including:
1) Solutions are homogeneous mixtures of two or more substances where the solute is dispersed uniformly throughout the solvent.
2) For a solution to form, the intermolecular forces between solute and solvent particles must be strong enough to overcome interactions between pure components.
3) The enthalpy change of dissolving depends on the energy changes of separating solute and solvent particles and forming new interactions between them.
The document discusses key concepts about solutions including:
1) Solutions are homogeneous mixtures of two or more substances where the solute is dispersed uniformly throughout the solvent.
2) For a solution to form, the intermolecular forces between solute and solvent particles must be strong enough to overcome interactions between pure components.
3) The enthalpy change of dissolving depends on the energy changes of separating solute and solvent particles and forming new interactions between them.
1. Solutions are homogeneous mixtures of two or more components, where the component present in smaller amounts is called the solute and the primary liquid component is the solvent.
2. Solutes can be electrolytes, which dissociate into ions, or nonelectrolytes, which do not dissociate. Common methods to express the concentration of solutions include molarity, molality, mole fraction, and percent composition.
3. The solubility of solids in liquids and gases in liquids depends on factors like temperature, pressure, and the nature of the solute and solvent. Henry's law and Raoult's law describe gas solubility and vapor pressure lowering in solutions. Ideal solutions follow
CBSE Class 12 Chemistry Chapter 2 (Solutions) | Homi InstituteHomi Institute
1) The solubility of solids in liquids is significantly affected by temperature changes, with solubility generally increasing as temperature decreases. Pressure does not significantly impact solubility.
2) According to Dalton's law of partial pressures, the total vapor pressure over a solution is equal to the sum of the partial pressures of the individual components in the solution.
3) Solutions can be classified as ideal or non-ideal based on whether they obey Raoult's law. Ideal solutions have zero enthalpy and volume changes upon mixing and the vapor pressure decreases linearly with changes in mole fractions.
Colligative properties of dilute solutions Manik Imran Nur Manik
lowering of vapour pressure, elevation of boiling point, depression of freezing point and osmotic pressure including necessary thermodynamic derivations.
Chapter 13 Lecture on Solutions & Colligative PropertiesMary Beth Smith
The document summarizes key concepts about solutions from chapters 11-13, including:
- Solutions are homogeneous mixtures of two or more substances where the solute is uniformly dispersed in the solvent.
- Solubility is affected by intermolecular forces - "like dissolves like" with polar substances dissolving in polar solvents.
- Temperature and pressure can impact solubility, with solubility generally increasing with temperature and gas solubility directly proportional to pressure.
- There are various ways to express concentration, including molarity, molality, mole fraction, ppm, and mass percentage.
1st Lecture on Solutions | Chemistry Part I | 12th ScienceAnsari Usama
This document discusses solutions and solubility. It defines solutions as homogeneous mixtures of two or more pure components consisting of a solvent and one or more solutes. Factors that affect solubility include the nature of the solute and solvent, temperature, and pressure. Solubility depends on intermolecular forces between solvent and solute molecules. Solutions can be ideal, obeying Raoult's law, or non-ideal, exhibiting positive or negative deviations from Raoult's law depending on relative solvent-solute and solvent-solvent interaction strengths.
1. The document contains questions and answers related to physical pharmaceutics including solubility, dissolution, distribution, and critical solution temperature.
2. Key concepts covered include Raoult's law, Henry's law, ideal and real solutions, factors that influence solubility, and applications of distribution law.
3. Methods of solute-solvent interactions are discussed including ionic, polar covalent, and non-polar interactions that influence whether dissolution occurs.
A solution is a homogeneous mixture composed of a solute dissolved in a solvent. In a solution, the solute is dissolved molecularly within the solvent. The properties of the solution are similar to those of the solvent. The concentration of a solution indicates how much solute is dissolved in a given amount of solvent. [END SUMMARY]
A solution is a homogeneous mixture of two or more substances. The component present in smaller amount is called the solute, while the component present in larger amount is called the solvent. Solutions can be categorized based on the physical state of the solute and solvent, and can be described using various concentration units including percentage by mass and volume, mole fraction, molality, and molarity. A solution's properties depend on factors like temperature, pressure, and composition. Raoult's law describes the behavior of solutions containing volatile liquid components.
This document provides information on solutions of non-electrolytes. It defines key terms like solute, solvent, saturated solution, and supersaturated solution. It explains how a solution forms via a 3 step process of solute separation, solvent separation, and solute-solvent interaction. Various methods of expressing concentration are described, including mass percentage, parts per million/billion, mole fraction, molarity, molality, and normality. Raoult's law and its limitations are discussed. Real solutions that deviate positively or negatively from Raoult's law are explained. Henry's law relating gas solubility to partial pressure is also summarized.
This document discusses several topics related to solutions, including:
1. It defines solutions and describes ways to express concentration such as molarity, mass percent, and mole fraction.
2. It explains that the enthalpy of solution depends on the energies required to separate the solute, expand the solvent, and allow interactions between solute and solvent particles. The overall enthalpy can be endothermic or exothermic.
3. Factors that affect solubility include like dissolving like, pressure, temperature, and molecular structure. Henry's law relates the solubility of gases to pressure. Temperature can either increase or decrease solubility depending on the substances involved.
This document discusses vapor pressure and solutions. It defines vapor pressure as the pressure exerted by vapor in equilibrium with its liquid or solid form. Vapor pressure depends on temperature and the nature of the liquid. Raoult's law states that the vapor pressure of a component in a solution is directly proportional to its mole fraction. Ideal solutions obey Raoult's law while non-ideal solutions deviate from it. Colligative properties depend only on the number of particles and include lowering of vapor pressure, elevation of boiling point, depression of freezing point, and osmotic pressure.
This document discusses solutions and various concepts related to solutions, including:
- Solutions occur when a solute dissolves in a solvent, with examples of different solvents and solutes.
- Common ways to measure concentration include molarity, mass percent, mole fraction, and molality.
- The heat of solution is determined by the energies of breaking apart the solvent and solute and mixing them.
- Factors like structure, pressure, temperature, and non-volatility of the solute affect solubility.
1. The document provides an overview of an advanced physical chemistry course taught by Dr. Fateh Eltaboni.
2. The course covers topics such as thermodynamics, kinetics, quantum mechanics, and spectroscopy.
3. Key concepts from the kinetic molecular theory are discussed, including how the random motion of gas molecules relates to measurable properties like pressure, temperature, and volume.
This document discusses the properties of solid state materials. It defines crystalline and amorphous solids, and describes the different types of crystal structures including simple cubic, body-centered cubic, and face-centered cubic. It also discusses crystal symmetry, unit cells, Bravais lattices, coordination number, X-ray crystallography, Bragg's law, and the different classifications of crystals based on bonding.
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This document contains lecture notes for an advanced photochemistry course taught by Dr. Fateh Eltaboni at the University of Benghazi. The 3-credit, 3-hour course covers fundamental photochemical principles, energy transfer processes, photochemical reactions and their quantum yields, photochemistry in nature, and special topics. The notes provide definitions of key photochemistry concepts, discuss light absorption and emission by molecules, and outline reaction types for carbonyl compounds under light, among other topics.
This document provides information on improving memory and discusses various techniques. It begins by defining memory as having three aspects: encoding, storage, and retrieval. It then discusses eidetic or photographic memory and notes that while not everyone has it, everyone can take steps to improve their memory. The document outlines 11 steps to improve memory, such as exercising one's brain regularly, reducing stress, eating a healthy diet, taking better pictures, repeating things to learn, and organizing one's life. It recommends several online resources and a book for further improving memory.
This document discusses colloids and macromolecules. It begins by defining colloids as mixtures where the dispersed particle diameter ranges from 10 to 2000 Angstroms. Colloids have two components - the dispersed phase and the dispersion medium. Colloids can be lyophilic, attracted to the dispersion medium, or lyophobic. Sols are lyophilic colloids where a solid is dispersed in a liquid. Macromolecules are very large molecules formed by polymerization. Their solutions exhibit properties like high viscosity and ability to be charged, making them behave similarly to colloids. The document then discusses various aspects of colloids and macromolecules like preparation methods, optical and electrical properties
This document contains lecture notes for a Physical Chemistry VIII course taught by Dr. Fateh Eltaboni at the University of Benghazi. The notes cover topics in photochemistry including characteristics of light, absorption of light, the Beer-Lambert law, photochemical reactions versus thermochemical reactions, quantum yield, and calculations related to photochemistry. Dr. Eltaboni provides examples and illustrations to explain key concepts in photochemistry.
This document discusses different types of materials including atoms, small molecules, and macromolecules. It describes how macromolecules are classified into natural and synthetic types, with examples of each. The document focuses on polymers as synthetic macromolecules, discussing their nomenclature, models of polymer chains, and various types of copolymers. It also examines the structures, configurations, and dynamics of macromolecules including random coil models.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
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This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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Physiology and chemistry of skin and pigmentation, hairs, scalp, lips and nail, Cleansing cream, Lotions, Face powders, Face packs, Lipsticks, Bath products, soaps and baby product,
Preparation and standardization of the following : Tonic, Bleaches, Dentifrices and Mouth washes & Tooth Pastes, Cosmetics for Nails.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
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A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
1. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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SOLUTIONS
CONTENTS
WAYS OF EXPRESSING CONCENTRATION: Molarity Molality Normality
SOLUTIONS OF GASES IN GASES: Henry‟s Law
SOLUTIONS OF LIQUIDS IN LIQUIDS:
SOLUBILITY OF COMPLETELY MISCIBLE LIQUIDS
SOLUBILITY OF PARTIALLY MISCIBLE LIQUIDS
VAPOUR PRESSURES OF LIQUID LIQUID SOLUTIONS
DISTILLATION: STEAM DISTILLATION
SOLUTIONS OF SOLIDS IN LIQUIDS
SOLUBILITY–EQUILIBRIUM CONCEPT
DETERMINATION OF SOLUBILITY
2. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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SOLUTION
Solution: It is a homogeneous mixture of two or more substances.
Solution consists of solute and solvent.
The constituent of the mixture present in a smaller amount is called the
Solute and the one present in a larger amount is called the Solvent.
For example, when a smaller amount of sugar (solute) is mixed with
water (solvent).
SOLUTION CONCENTRATION:
The concentration of a solution is defined as : the amount of solute
present in a given amount of solution.
Concentration is generally expressed as:
A solution containing low concentration of solute is called DILUTE
SOLUTION. A solution of high concentration is called CONCENTRATED
SOLUTION.
3. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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TYPES OF SOLUTIONS:
WAYS OF EXPRESSING CONCENTRATION:
(1) Per cent by weight (wt%)
(2) Mole fraction (x)
(3) Molarity (M)
(4) Molality (m)
4. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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(5) Normality (N)
(1) Per cent by weight (wt%)
For example: if a solution of HCl contains 36 per cent HCl by weight, it
has 36 g of HCl for 100 g of solution.
(2) Mole fraction (x)
5. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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(3) Molarity (M)
For 1 mole of solute dissolved in one litre of solution: M = 1 i . e.,
molarity is one. Such a solution is called 1 M (read “1 molar”). A
solution containing 2 moles of solute in one litre is 2M (“two molar”);
and so on. Unit of molarity is mol litre–1
6. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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.
(4) Molality (m)
A solution obtained by dissolving one mole of the solute in 1000 g of
solvent is called one molal or 1 m solution.
7. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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(5) Normality (N)
Thus, if 40 g of NaOH (eq. wt. = 40) be dissolved in one litre of solution,
normality of the solution is one and the solution is called 1 N (one-
normal). A solution containing 4.0 g of NaOH is 0.1 N.
8. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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SOLUTIONS OF GASES IN GASES:
When a gas is mixed with another gas a completely homogeneous
solution results.
PROPERTIES OF GASEOUS SOLUTIONS:
(1) Complete miscibility.
When one gas is dissolved in another gas they form a
homogeneous solution.
9. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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(2) Dalton‟s law of Partial pressures.
The total pressure exerted by a gaseous mixture is the sum of the
partial pressures of the component gases.
If p1, p2 ,p3 are the partial pressures of the constituents, the total
pressure PT of the mixture is given by:
PT = p1 + p2 + p3
HENRY‟S LAW:
The solubility of a gas in a solvent depends on the pressure and the
temperature.
When a gas is in saturated solution, the following equilibrium exists:
gas gas in solution
If pressure is increased on the system, the equilibrium will move in the
direction which will reduce the pressure (Le Chatelier Principle).
The pressure can be reduced by more gas dissolving in solvent. Thus
solubility or concentration of a gas in a given solvent is increased with
increase of pressure.
10. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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Henry‟s Law: for a gas in contact with a solvent at constant
temperature, concentration of the gas that
dissolves in the solvent is directly proportional to the pressure of the
gas.
Mathematically, Henry‟s Law may be expressed as:
Cα P
C = k P
Where k is Henry‟s Law constant depends on the nature of the gas
and solvent, and the units of P and C used.
12. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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SOLUTIONS OF LIQUIDS IN LIQUIDS:
1. SOLUBILITY OF COMPLETELY MISCIBLE LIQUIDS:
Liquids like alcohol and water mix in all proportions and they could be
compared to gases.
2. SOLUBILITY OF PARTIALLY MISCIBLE LIQUIDS:
A large number of liquids are known which dissolve in one another
only to a limited extent e . g ., ether and water. Ether dissolves about
1.2% water; and water also dissolves about 6.5% ether.
When equal volumes of ether and water are shaken together, two
layers are formed, one of a saturated solution of ether in water and
the other of a saturated solution of water in ether.
STUDY THE EFFECT OF TEMPERATURE ON THE COMPOSITION OF
SUCH MIXTURES WITH REFERENCE TO THREE TYPICAL SYSTEMS:
(1) Phenol-Water system
(2) Triethylamine-Water system
(3) Nicotine-Water system
13. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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The temperature at which the two solutions layers merge into one
another to from one layer, is called the Critical Solution Temperature
(CST)
VAPOUR PRESSURES OF LIQUID–LIQUID SOLUTIONS:
The study of the vapour pressures of mixtures of completely miscible
liquids at constant temperature help in the separation of the liquids by
fractional distillation.
14. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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By plotting the vapour pressure against composition it has been
revealed that mixtures of the miscible liquids are of three types:
1. First Type of Mixtures of Miscible Liquids: complete separation of
this type of solutions into components is impossible.
2. Second Type of Mixtures of Miscible Liquids: it is not possible to
effect a complete separation by fractional distillation
3. Third Type of Mixtures of Miscible Liquids: we can completely
separate the components by fractional distillation.
THEORY OF FRACTIONAL DISTILLATION:
Fractional distillation is the separation of a mixture into its
component parts, or fractions, such as in separating chemical
compounds by their boiling point by heating them to
atemperature at which one or more fractions of the compound
will vaporize. It is a special type of distillation. Generally the
15. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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component parts boil at less than 25 °C from each other under a
pressure of one atmosphere. If the difference in boiling points is
greater than 25 °C, a simple distillation is used.
The efficiency of fractional distillation is considerably enhanced by the
use of the Fractionating columns.
17. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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STEAM DISTILLATION:
Distillation carried in a current of steam is called steam distillation.
Steam distillation is used for purification of organic liquids which are
steam volatile and immiscible with water ( e. g., aniline).
THEORY OF STEAM DISTILLATION:
The vapour pressure of a liquid increases with increase of
temperature. When the vapour pressure equals the atmospheric
pressure, the temperature recorded is the boiling point of the given
liquid. In case of a mixture of two immiscible liquids, each component
exert its own vapour pressure as if it were alone. The total vapour
pressure over the mixture (P) is equal to the sum of the individual
vapour pressures (p1, p2) at that temperature.
P = p1 + p2
Hence the mixture will boil at a temperature when the combined
vapour pressure P, equals the atmospheric pressure. Since P > p1 or
p2, the boiling point of the mixture of two liquids will be lower than
either of the pure components.
18. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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SOLUTIONS OF SOLIDS IN LIQUIDS:
The process of solution of a solid substance in a solvent is explained by
the electrical forces operating between the molecules or ions of the
solute and the molecules of the solvent.
Polar solutes dissolve easily in polar solvents while they remain
insoluble in non-polar solvents. For example, sodium chloride (an
electrolyte) is soluble in water which is highly polar solvent, while it is
insoluble in a non-polar solvent like chloroform.
The sodium chloride (NaCl) dissolves in water to give Na+
and Cl–
ions.
The Na+
ion is solvated (hydrated) to have around a layer of water
molecules.
19. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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DISSOLUTION DUE TO HYDROGEN BONDING:
SOLUBILITY–ITS EQUILIBRIUM CONCEPT:
(1) Dissolution – the particles of the solute leaving the solid and
passing into solution.
( 2) Recrystallisation – the particles of the solute returning from the
solution and precipitating on the solid.
(dynamic equilibrium)
20. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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THE SOLUBILITY is defined as the concentration of the solute in
solution when it is in equilibrium with the solid substance at a
particular temperature.
THE SATURATED SOLUTION is defined as one which is in equilibrium
with the excess of solid at a particular temperature.
THE SUPERSATURATED SOLUTION is a solution which would contain
more solute than the saturated solution at that temperature.
DETERMINATION OF SOLUBILITY:
The solubility of a substance is determined by preparing its saturated
solution and then finding the concentration by evaporation or a
suitable chemical method.
SOLUBILITY CURVES:
A curve drawn between solubility and temperature is termed Solubility
Curve.
THE SOLUBILITY CURVES ARE TWO TYPES:
(1) Continuous solubility curves (2) Discontinuous solubility curves
21. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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THEORY OF DILUTE SOLUTIONS
CONTENTS
COLLIGATIVE PROPERTIES: LOWERING OR VAPOUR PRESSURE: RAOULT‟S LAW
MEASUREMENT OF LOWERING OF VAPOUR PRESSURE: (1) Barometric Method
(2) Manometric Method
(3) Ostwald and Walker‟s Dynamic Method
BOILING POINT ELEVATION: Relation between Boiling-point elevation and Vapour-
pressure lowering
MEASUREMENT OF BOILING POINT ELEVATION: (1) Landsberger-Walker Method
(2) Cottrell‟s Method
FREEZING-POINT DEPRESSION
MEASUREMENT OF FREEZING-POINT DEPRESSION: (1) Beckmann‟s Method
(2) Rast‟s Camphor Method
COLLIGATIVE PROPERTIES OF ELECTROLYTES
22. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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COLLIGATIVE PROPERTIES
Dilute solutions containing non-volatile solute exhibit the following
properties:
(1) Lowering of the Vapour Pressure
(2) Elevation of the Boiling Point
(3) Depression of the Freezing Point
(4) Osmotic Pressure
Colligative Properties: (Greek colligatus = Collected together).
Its defined as property which depends on the number of particles in
solution and not on the size or chemical nature of the particles
Each colligative property is related to any other.
The colligative properties are used to measure the molecular
weights of the dissolved substances.
LOWERING OF VAPOUR PRESSURE: RAOULT‟S LAW
23. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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P is the vapour pressure of the pure solvent and P is the pressure of
the solution. (P-Ps) is the lowering of vapour pressure.
Raoult‟s Law: the relative lowering of the vapour pressure of a dilute
solution is equal to the mole fraction of the solute present in dilute
solution.
IDEAL SOLUTIONS AND DEVIATIONS FROM RAOULT‟S LAW:
A solution which obeys Raoult‟s law strictly is called an Ideal
solution.
A solution which shows deviations from Raoult‟s law is called a
Nonideal or Real solution.
24. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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Determination of Molecular Mass from Vapour Pressure Lowering:
If in a determination w grams of solute are dissolved in W grams of the
solvent, m and M are molecular masses of the solute and solvent
respectively, we have:
26. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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MEASUREMENT OF LOWERING OF VAPOUR PRESSURE:
(1) Barometric Method
Measuring the individual vapour pressure
of a liquid and then the solution
This method is not accurate as the lowering
of vapour pressure is too small.
(2) Manometric Method
The air in the connecting tube removed by a vacuum pump.
The manometric liquid can be mercury or n-butyl phthalate which
has low density and lowvolatility .
27. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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ELEVATION OF BOILING POINT:
Relation between Elevation of Boiling Point and Lowering of Vapour-
pressure:
When a liquid is heated, its vapour pressure rises and when it
equals the atmospheric pressure, the liquid boils.
The addition of a non volatile solute lowers the vapour pressure
and consequently elevates the boiling point as the solution has to
be heated to a higher temperature to make its vapour pressure
become equal to atmospheric pressure.
If Tb is the boiling point of the solvent and T is the boiling point of
the solution, the difference in the boiling points (ΔT) is called the
elevation of boiling point.
Determination of Molecular Mass from Elevation of Boiling Point:
28. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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where Kb is a constant called Boiling point constant or Ebulioscopic
constant of molal elevation constant. If w/ m = 1, W = 1, Kb = ΔT .
and the units of Kb are :
29. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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MEASUREMENT OF BOILING–POINT ELEVATION:
(1) Landsberger-Walker Method
(2) Cottrell‟s Method
30. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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FREEZING–POINT DEPRESSION
The difference of the freezing point of the pure solvent and the solution
is referred to as the Depression of freezing point. It is represented by
the symbol ΔT or ΔTf.
Determination of Molecular Weight from Depression of Freezing point:
Where Kf is a constant called Freezing-point constant or Cryoscopic
constant or Molal depression constant. If w /m = 1 and W = 1, Kf =
ΔT.
31. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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MEASUREMENT OF FREEZING–POINT
DEPRESSION
(1) Beckmann‟s Method (1903):
(2) Rast‟s Camphor Method
32. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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COLLIGATIVE PROPERTIES OF ELECTROLYTES
The electrolytes ionize and yield more than one particle per
formula unit in solution. Therefore, the colligative effect of an
electrolyte solution is always greater than that of a nonelectrolyte
of the same molal concentration.
Van‟t Hoff factor (i): its the ratio of the colligative effect produced
by an electrolyte solution to the effect for the same concentration
of a nonelectrolyte solution.
is the freezing-point depression for the electrolyte. is the
value of depression of freezing-point of the electrolyte solution
assuming no ionization (nonelectrolyte).
33. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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ABNORMAL MOLECULAR MASSES OF ELECTROLYTES:
Since the value of (i) is always greater than 1 the experimental
molecular weight will always be less than the theoretical value
calculated from the formula.
Relation Between van‟t Hoff Factor (i) and Degree of Dissociation (α):
v is number of ions produced
34. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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CONCEPT OF ACTIVITY AND ACTIVITY COEFFICIENT:
The experimentally determined value of concentration whether of
is less than the actual concentration.
The „activity‟: its the effective concentration of a molecule or ion in a
solution. Activity coefficient (γ) is:
36. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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OSMOSIS AND OSMOTIC PRESSURE
CONTENTS
WHAT IS OSMOSIS? The Egg Experiment Silica Garden
SEMIPERMEABLE MEMBRANES Preparation of Cupric ferrocyanide membrane
OSMOTIC PRESSURE Pfeffer‟s Method Berkeley and Hartley‟s Method A Modern
Osmometer
ISOTONIC SOLUTIONS THEORIES OF OSMOSIS Molecular Sieve Theory Membrane
Solution Theory Vapour Pressure Theory Membrane Bombardment Theory
REVERSE OSMOSIS Desalination of Sea Water
LAWS OF OSMOTIC PRESSURE Boyle-van‟t Hoff Law for Solutions
Charles‟-van‟t Hoff Law for Solutions Van‟t Hoff Equation for Solutions
Avogadro-van‟t Hoff Law for Solutions VAN‟T HOFF THEORY OF DILUTE SOLUTIONS
CALCULATION OF OSMOTIC PRESSURE DETERMINATION OF MOLECULAR WEIGHT
RELATION BETWEEN VAPOUR PRESSURE AND OSMOTIC PRESSURE
OSMOTIC PRESSURE OF ELECTROLYTES
37. Physical Chemistry VI (Solutions & Electrochemistry) Dr Fateh Eltaboni
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WHAT IS OSMOSIS?
The flow of the solvent through a semipermeable membrane from
pure solvent to solution, or from a dilute solution to concentrated
solution, is termed Osmosis (Greek Osmos = to push).
COMPARISON BETWEEN DIFFUSION AND OSMOSIS
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OSMOSIS EXPERIMENTS
1. Thistle Funnel Experiment:
The phenomenon of osmosis can be demonstrated by fastening a
piece of cellophane over a thistle funnel as shown in Fig. 16.3. A
concentrated aqueous sugar solution is placed inside the thistle
funnel which is then immersed in water. The osmosis takes place
through the semipermeable membrane from water to the sugar
solution. The flow of water into the funnel shows up as the
solution is seen rising in the tube remarkably.
2. The Egg Experiment:
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The outer hard shell of two eggs of the same size is removed by
dissolving in dilute HCl. One of these is placed in distilled water
and the other in saturated salt solution. After a few hours it will be
noticed that the egg placed in water swells and the one in salt
solution shrinks. In the first case, water diffuses through the skin
(a semipermeable membrane) into the egg material which swells.
In the second case, the concentration of the salt solution being
higher than the egg material, the egg shrinks.
WHAT IS OSMOTIC PRESSURE?
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The hydrostatic pressure built up on the solution which just stops
the osmosis of pure solvent into the solution through a
semipermeable membrane, is called Osmotic Pressure.
Another definition:
Osmotic pressure may be defined as the external pressure
applied to the solution in order to stop the osmosis of solvent into
solution separated by a semipermeable membrane.
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DETERMINATION OF OSMOTIC PRESSURE
The osmotic pressure of a given solution can be determined
experimentally by the methods detailed below. The apparatus
used for the purpose is often referred to as osmometer.
(1) Pfeffer‟s Method:
(2) Berkeley and Hartley‟s Method:
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(3) A Modern Osmometer:
ISOTONIC (ISO-OSMOTIC) SOLUTIONS
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When two solutions are separated by a semipermeable
membrane and there is no flow of water across the membrane,
the solutions are said to be Isotonic.
THEORIES OF OSMOSIS
(1) The Molecular Sieve Theory:
Smaller solvent molecules can pass through the pores but the
larger molecules cannot.
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(2) Membrane Solution Theory
Membrane proteins bearing functional groups such as – COOH, –
OH, – NH2, etc., dissolve water molecules by hydrogen bonding or
chemical interaction. Thus membrane dissolves water from the
pure water (solvent) forming what may be called „membrane
solution‟.
(3) Vapour Pressure Theory:
REVERSE OSMOSIS
Desalination of Sea Water by Hollow-fibre Reverse Osmosis:
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LAWS OF OSMOTIC PRESSURE
(1) Boyle-van‟t Hoff Law for Solutions:
(2) Charles-van‟t Hoff Law for Solutions:
at constant pressure
(3) Van‟t Hoff Equation for Solutions:
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(4) Avogadro-van‟t Hoff Law for Solutions:
CALCULATION OF OSMOTIC PRESSURE
All gas laws may be considered to apply to dilute solutions rigidly.
This gives an easy solution to problems on osmotic pressure.
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DETERMINATION OF MOLECULAR WEIGHT FROM OSMOTIC
PRESSURE
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RELATION BETWEEN VAPOUR PRESSURE AND OSMOTIC PRESSURE
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OSMOTIC PRESSURE OF ELECTROLYTES
Like other colligative properties, observed osmotic pressure of
electrolytes (π ) in aqueous solutions is higher than the value
calculated using van‟t Hoff equation, π0V = nRT . Expressing in
terms of van‟t Hoff factor (i):
Van‟t Hoff Equation for Solutions of Electrolytes:
For example, if NaCl is ionized completely as at infinite dilution, 1
mole of NaCl will give 2 moles of particles (Na+
and Cl–
, one mole
each). Therefore, the observed osmotic pressure will be twice the
calculated value for no ionization. That is,
Similarly, the value of i for CaCl2 at infinite dilution will be 3; for
FeCl3 it will be 4.
If electrolytes are partially ionized in aqueous solution. α be the
degree of ionization for a salt AB,
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ELECTROLYSIS AND ELECTRICAL CONDUCTANCE
CONTENTS
Electrolysis and Electrical Conductance MECHANISM OF ELECTROLYSIS ELECTRICAL UNITS
FARADAY’S LAWS OF ELECTROLYSIS FARADAY’S FIRST LAW FARADAY’S SECOND LAW
IMPORTANCE OF THE FIRST LAW OF ELECTROLYSIS IMPORTANCE OF THE SECOND LAW OF ELECTROLYSIS
CONDUCTANCE OF ELECTROLYTES SPECIFIC CONDUCTANCE EQUIVALENT CONDUCTANCE
SUMMARY OF ELECTROCHEMICAL QUANTITIES STRONG ELECTROLYTES WEAK ELECTROLYTES
MEASUREMENT OF ELECTROLYTIC CONDUCTANCE DETERMINATION OF THE CELL CONSTANT
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Water-soluble substances are distinguished as electrolytes or
nonelectrolytes.
Electrolytes are electrovalent substances that form ions in
solution which conduct an electric current. NaCl, CuSO4 and
KNO3 are examples of electrolytes.
Nonelectrolytes are covalent substances which furnish neutral
molecules in solution. Their water-solutions do not conduct an
electric current. Sugar, alcohol and glycerol are typical
nonelectrolytes.
Electrolysis The decomposition of an electrolyte by passing
electric current through its solution is termed Electrolysis ( lyo =
breaking).
Electrolytic cell. The cell contains water-solution of an electrolyte
in which two metallic rods (electrodes) are dipped .These rods
are connected to the two terminals of a battery (source of
electricity). The electrode connected to the positive terminal of
the battery attracts the negative ions (anions) and is called
anode. The other electrode connected to the negative end of the
battery attracts the positive ions (cations) and is called cathode.
MECHANISM OF ELECTROLYSIS
Example: Let us consider the electrolysis of hydrochloric acid as
an example. In solution, HCl is ionised
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In the electrolytic cell Cl–
ions will move toward the anode and H+
ions will move toward the cathode. At the electrodes, the
following reactions will take place.
At cathode:
At anode:
Overall reaction:
ELECTRICAL UNITS
Coulomb
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1. A coulomb is a unit of electricity. It is the amount of electricity
which will deposit 0.001118 gram of silver from a 15 per cent
solution of silver nitrate in a coulometer.
2. Ampere is a unit rate of flow of electricity. It is that current which
of silver in one second. In other words, an ampere is a current of
one coulomb per second.
3. Ohm is a unit of electrical resistance.
4. Volt is a unit of electromotive force. It is the difference in
electrical potential required to send a current of one ampere
through a resistance of one ohm.
FARADAY‟S LAWS OF ELECTROLYSIS
If m is the mass of substance (in grams) deposited on electrode
by passing Q coulombs ofelectricity, then
(First law)
We know that Q = I × t, where I is the strength of current in
amperes and t is the time in second. Therefore,
(Second law)
Where Z is the constant known as the Electrochemical equivalent
of the substance (electrolyte).
THE ELECTRICAL UNIT FARADY:
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VERIFICATION OF THE SECOND LAW OF ELECTROLYSIS
According to this law when the same quantity of electricity is
passed through different electrolyte solutions, the masses of the
substances deposited on the electrodes are proportional to their
chemical equivalents.
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To verify the law, let us take an arrangement of the type shown in
Fig. 24.2. Pass the same quantity of electricity through the three
coulometers (the term „coulometer‟ is now in practice replaced
by the older term „voltameter‟) containing solution of dilute
H2SO4, CuSO4 and AgNO3.
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CONDUCTANCE OF ELECTROLYTES
Electrolyte solutions conduct electric current by movement of the
ions to the electrodes. The power of electrolytes to conduct
electric currents is termed conductivity or conductance.
Like metallic conductors, electrolytes obey Ohm‟s law.
According to this law, the current I flowing through a metallic
conductor is given by the relation:
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Where E is the potential difference at two ends (in volts); and R
is the resistance measured in ohms (or Ω). The resistance R of a
conductor is directly proportional to its length, l, and inversely
proportional to the area of its cross-section, A . That is,
Where ρ “rho” is a constant of proportionality and is called
resistivity or specific resistance. Its value depends upon the
material of the conductor. From above we can write:
Specific resistance: It is the resistance in ohms which one
centimetre cube of it offers to the passage of electricity
Specific conductance or Specific conductivity.
It is defined as: the conductance of one centimetre cube (cc) of a
solution of an electrolyte.
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Units of Specific conductance:
or
The specific conductance increases with : (i) ionic concentration,
and (ii) speeds of the ions concerned.
Equivalent Conductance ():
It is defined as the conductance of an electrolyte obtained by
dissolving one gram-equivalent of it in V cc of water.
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Variation of Equivalent conductance with Concentration (or Dilution):
Strong electrolytes are completely ionised at all concentrations
(or dilutions). But weak electrolytes are partially ionised.
The increase in equivalent conductance is not due to the increase
in the number of current carrying species. This is, in fact, due to
the decrease in forces of attraction between the ions of opposite
charges with the decrease in concentration (or increase in
dilution). At higher concentration, the forces of attraction
between the opposite ions increase
Consequently, it affects the speed of the ions with which they
move towards oppositely charged electrodes. This phenomenon
is called ionic interference.
As the solution becomes more and more dilute, the equivalent
conductance increases, till it reaches a limitary value. This value
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is known as equivalent conductance at infinite dilution (zero
concentration) and is denoted by 0.
Weak electrolytes have low ionic concentrations and hence
interionic forces are negligible. Ionic speeds are not affected with
decrease in concentration (or increase in dilution). The increase
in equivalent conductance with increasing dilution is due to the
increase in the number of current-carrier species. In other
words, the degree of ionisation (α) increases.
Thus increase in equivalent conductance (Λ) in case of a weak
electrolyte is due to the increase in the number of ions.
In case of a weak electrolyte Λ∝ is the equivalent conductance
when ionisation is complete. So, the conductance ratio Λ / Λ∝ is
the degree of ionisation. That is,
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Molar Concentration (μ):
It is defined as : the conductance of all ions produced by one
mole of an electrolyte when dissolved in a certain volume V cc.
Upon dilution specific conductance decreases, while Equivalent
conductance and Molar conductance increases.
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Variation of Conductance with Temperature:
The conductance of a solution of an electrolyte generally
increases with rise in temperature. For example, the
conductances of 0.1 M KCl at two different temperatures are
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The conductance of a given electrolyte depends on two factors :
1. The number of ions present in unit volume of solution
2. The speed at which ions move towards the electrodes
At a given temperature, the first factor remains the same for a
particular electrolyte. Thus the increase in conductance with rise
in temperature is due to the influence of factor (2). With rise in
temperature the viscosity of the solvent (water) decreases which
makes the ions to move freely toward the electrodes.
For weak electrolytes, the influence of temperature on
conductance depends upon the value of ΔH accompanying the
process of ionisation. If the ionisation is exothermic (–ΔH), the
degree of ionisation is less at higher temperature (Le Chatelier‟s
principle) and conductance decreases.Conversely, if the
ionisation is endothermic (+ ΔH), the degree of ionisation is more
at higher temperature and conductance increases.
STRONG AND WEAK ELECTROLYTES
Electrolytes may be divided into two classes :
1. Strong electrolytes
2. Weak electrolytes
1. Strong Electrolytes
A strong electrolyte is a substance that gives a solution in which
almost all the molecules are ionised. The solution itself is called a
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strong electrolytic solution. Such solutions are good conductors
of electricity and have a high value of equivalent conductance
even at low concentrations. The strong electrolytes are :
2. Weak Electrolytes:
A weak electrolyte is a substance that gives a solution in which
only a small proportion of the solute molecules are ionised. Such
a solution is called a weak electrolytic solution, that has low
value of equivalent conductance. The weak electrolytes are:
MEASUREMENT OF ELECTROLYTIC CONDUCTANCE
The conductance is the reciprocal of resistance. Therefore it can
be determined by measuring the resistance of the electrolytic
solution. This can be done in the laboratory with the help of a
Wheatstone bridge.The solution whose conductance is to be
determined is placed in a special type of cell known as the
conductance cell.
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DETERMINATION OF THE CELL CONSTANT
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To determine the cell constant, a standard solution of KCl whose
specific conductance at a given temperature is known, is used.
Then a solution of KCl of the same strength is prepared and its
conductance determined experimentally at the same
temperature. Substituting the two values in the above expression,
the cell constant can be calculated.
For example, according to Kohlrausch the specific conductance
of N/50 solution at 25ºC is 0.002765 mho. Now, an N/50 solution of
KCl is prepared by dissolving 0.372 g pure KCl in 250 cc „extra-
pure‟ water (conductance water) and its conductance
determined at 25ºC. The cell constant is then calculated by
substituting the observed conductance in the expression.