prepared notes as pre Tanzanian syllabus by Mr Saad Miraji a bachelor degree holder in science with education (chemistry and biology) currently teaching at Shamsiye boys secondary school advance chemistry
Potentiometry is an electroanalytical technique that uses potentiometers to measure electrochemical potential. It involves using reference and indicator electrodes immersed in analyte solutions. The potential difference between the electrodes depends on ion activity/concentration based on the Nernst equation, allowing for quantitative analysis. A salt bridge containing a neutral salt maintains electrical neutrality between electrode half-cells. Common reference electrodes include silver/silver chloride and saturated calomel electrodes. Potentiometry is used for pH measurements and potentiometric titrations.
1) Electrochemical cells can be used to monitor redox reactions by measuring the electric current produced which is proportional to the rate of reaction. Batteries produce direct current by converting chemical energy to electrical energy through redox reactions.
2) A redox titration uses the transfer of electrons between analyte and titrant during a redox reaction. Oxidation involves losing electrons and reduction involves gaining electrons.
3) The Nernst equation is used to calculate the reduction potential under non-standard conditions when concentrations are not equal to 1M.
The document discusses the differences between a potentiometer and a voltmeter. A potentiometer can measure the electromotive force (emf) of a cell very accurately in a null deflection method without drawing any current from the cell. A voltmeter can only measure emf approximately and does draw current, meaning it has a lower sensitivity. The document also provides details on the construction, working principle, and applications of a potentiometer.
Coulometry and electrogravimetric analysis are analytical techniques that involve completely oxidizing or reducing an analyte through electrolysis. In coulometry, the quantity of electrical charge passed is measured and related to the amount of analyte present. In electrogravimetry, the analyte is converted electrolytically into a product that is weighed to determine the analyte amount. Both techniques are accurate and precise, but require ensuring all current passed results in analyte oxidation/reduction. Controlled-potential coulometry uses a constant potential, while controlled-current coulometry applies a constant current, each with their own experimental considerations to achieve complete analyte conversion.
Electrochemistry studies chemical reactions at the interface between an electrode and an electrolyte. Oxidation occurs when an element loses electrons and reduction occurs when an element gains electrons. Galvanic cells produce electrical energy from spontaneous redox reactions. The Nernst equation relates cell potential to concentration. Faraday's laws state that the amount of reaction is proportional to charge and equivalent weights determine amounts deposited. Electrolysis is used industrially to refine and deposit metals.
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 document discusses electrochemistry and provides definitions and examples of key concepts. It defines oxidation as the loss of electrons and reduction as the gain of electrons. An electrochemical reaction is one where a chemical reaction produces an electric current or where an electric current causes a chemical reaction. There are two types of electrochemical cells - galvanic cells where a chemical reaction produces a current, and electrolytic cells which use electricity to drive a non-spontaneous reaction. The document also discusses standard electrode potentials and how they are used to calculate cell emf and predict reaction spontaneity. Industrial applications of electrochemical cells mentioned include electrolysis, chloralkali production, and metal extraction from ores.
Electrogravimetry is a method used to separate and quantify ions of a substance, usually a metal, through electrolysis. The analyte solution is electrolyzed, causing the analyte to deposit on the cathode. The cathode is weighed before and after the experiment, and the mass difference is used to calculate the amount of analyte originally present. There are two types of electrogravimetry - constant current electrolysis, where the current is kept constant, and constant potential electrolysis, where the potential is kept constant. In both cases, the deposited analyte on the cathode is measured through changes in mass to determine the concentration in the original solution.
Potentiometry is an electroanalytical technique that uses potentiometers to measure electrochemical potential. It involves using reference and indicator electrodes immersed in analyte solutions. The potential difference between the electrodes depends on ion activity/concentration based on the Nernst equation, allowing for quantitative analysis. A salt bridge containing a neutral salt maintains electrical neutrality between electrode half-cells. Common reference electrodes include silver/silver chloride and saturated calomel electrodes. Potentiometry is used for pH measurements and potentiometric titrations.
1) Electrochemical cells can be used to monitor redox reactions by measuring the electric current produced which is proportional to the rate of reaction. Batteries produce direct current by converting chemical energy to electrical energy through redox reactions.
2) A redox titration uses the transfer of electrons between analyte and titrant during a redox reaction. Oxidation involves losing electrons and reduction involves gaining electrons.
3) The Nernst equation is used to calculate the reduction potential under non-standard conditions when concentrations are not equal to 1M.
The document discusses the differences between a potentiometer and a voltmeter. A potentiometer can measure the electromotive force (emf) of a cell very accurately in a null deflection method without drawing any current from the cell. A voltmeter can only measure emf approximately and does draw current, meaning it has a lower sensitivity. The document also provides details on the construction, working principle, and applications of a potentiometer.
Coulometry and electrogravimetric analysis are analytical techniques that involve completely oxidizing or reducing an analyte through electrolysis. In coulometry, the quantity of electrical charge passed is measured and related to the amount of analyte present. In electrogravimetry, the analyte is converted electrolytically into a product that is weighed to determine the analyte amount. Both techniques are accurate and precise, but require ensuring all current passed results in analyte oxidation/reduction. Controlled-potential coulometry uses a constant potential, while controlled-current coulometry applies a constant current, each with their own experimental considerations to achieve complete analyte conversion.
Electrochemistry studies chemical reactions at the interface between an electrode and an electrolyte. Oxidation occurs when an element loses electrons and reduction occurs when an element gains electrons. Galvanic cells produce electrical energy from spontaneous redox reactions. The Nernst equation relates cell potential to concentration. Faraday's laws state that the amount of reaction is proportional to charge and equivalent weights determine amounts deposited. Electrolysis is used industrially to refine and deposit metals.
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 document discusses electrochemistry and provides definitions and examples of key concepts. It defines oxidation as the loss of electrons and reduction as the gain of electrons. An electrochemical reaction is one where a chemical reaction produces an electric current or where an electric current causes a chemical reaction. There are two types of electrochemical cells - galvanic cells where a chemical reaction produces a current, and electrolytic cells which use electricity to drive a non-spontaneous reaction. The document also discusses standard electrode potentials and how they are used to calculate cell emf and predict reaction spontaneity. Industrial applications of electrochemical cells mentioned include electrolysis, chloralkali production, and metal extraction from ores.
Electrogravimetry is a method used to separate and quantify ions of a substance, usually a metal, through electrolysis. The analyte solution is electrolyzed, causing the analyte to deposit on the cathode. The cathode is weighed before and after the experiment, and the mass difference is used to calculate the amount of analyte originally present. There are two types of electrogravimetry - constant current electrolysis, where the current is kept constant, and constant potential electrolysis, where the potential is kept constant. In both cases, the deposited analyte on the cathode is measured through changes in mass to determine the concentration in the original solution.
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The document discusses kinetics of electrochemical reactions and mass transfer in electrochemical systems. It covers the following key points:
1) Chemical kinetics is the study of reaction rates and mechanisms. In industrial synthesis, reaction rates are as important as equilibrium constants. Kinetics answers how fast reactions occur, while thermodynamics addresses if they will occur.
2) Applying a potential increases the reaction rate by reducing the activation energy barrier. Current increases with increasing driving force from an applied potential. Catalysts also reduce the activation energy.
3) The rate of electrochemical reactions depends on parameters like materials, composition, and temperature. Increasing the reaction rate improves fuel cell performance. Reactions occur at electrode-elect
Electrogravimetry involves the electrolytic deposition of an element onto an electrode, which is then weighed before and after deposition to determine the amount deposited. There are two main methods - constant current electrolysis, where current is kept constant and potential varies, and constant potential electrolysis, where potential is kept constant. Electrogravimetry can be used to determine the concentration of elements in solutions and to separate elements electrolytically based on their deposition potentials. It has applications in quantitative analysis, electrosynthesis, separating species in solutions, and purifying reagents.
Potentiometry uses a reference electrode and an indicator electrode to measure the potential difference in a sample solution. When the electrodes are placed in the solution, the potential is generated based on the concentration of ions present. There are several types of potentiometric titrations including acid-base, redox, complexometric, and precipitation titrations. Potentiometry has many applications in fields like clinical chemistry, environmental analysis, potentiometric titrations, agriculture, detergent manufacturing, food processing and more. It is used to analyze important ions and determine equivalence points during titrations.
This document summarizes the key electrical properties of metals and semiconductors. It discusses Ohm's law and how electrical conductivity in metals is influenced by drift velocity and current density. It also explains how resistivity is related to temperature in metals. For semiconductors, it describes the band structure of insulators, metals and semiconductors and how conductivity varies with intrinsic carrier concentration and temperature in intrinsic semiconductors. It then discusses the effects of doping on carrier concentrations and conductivity in n-type and p-type extrinsic semiconductors. Finally, it provides an overview of compound semiconductors made of two or three elements.
This document discusses devices used in electrochemical analysis and auxiliary laboratory devices. It describes galvanic cells, electrodes, and potentiometric devices used to determine ionic composition. It also discusses auxiliary devices like centrifuges and thermostats. Conductometers and coulometers are described which measure conductivity by applying a low voltage alternating current between electrodes to avoid electrolysis. pH meters and glass electrodes are summarized which can directly measure pH by relating the electrode voltage to hydrogen ion concentration.
This document provides an overview of electrochemistry techniques used in clinical chemistry, including potentiometry, voltammetry, coulometry, and conductometry. It describes the basic concepts such as electrochemical cells and electrodes. Potentiometry techniques like ion-selective electrodes and their applications in measuring electrolytes are discussed in detail. Other techniques like amperometry and different types of voltammetry and coulometry are also summarized along with their uses and advantages.
pH and Potentiometry, Potentiometric titrations, Electrodes used in Potentiometry, Standard Hydrougen electrode, calamel electrode, silver silver chloride electrode, glass electrode
1. The document discusses experimental methods to verify the validity of the Debye-Hückel and Onsager equations, which describe electrolyte behavior at high dilutions.
2. Using liquid membrane cells, studies were able to examine dilutions as high as 10-4 M and found that the Debye-Hückel equation holds for 1:1 electrolytes but shows negative deviations for 2:2 or 3:2 electrolytes.
3. Conductance measurements of various electrolytes at different temperatures found close agreement with the Onsager equation at low concentrations, validating it as accurately describing conductance behavior at high dilutions.
This document discusses electrogravimetry, which is the quantitative analysis of substances by electrolysis. It defines key terms used in electrogravimetry like cathode, anode, current density, and overpotential. It explains Faraday's laws of electrolysis and how they relate to the amount of material deposited. It also describes how controlling variables like cathode potential can be used to selectively deposit metals and separate them from each other.
Potentiometry is an electroanalytical technique that measures the electric potential of electrochemical cells under zero-current conditions. It involves measuring the potential difference between a reference electrode with a known potential and an indicator electrode whose potential varies with the concentration of the analyte ion. The potential difference is used to determine analyte concentration based on the Nernst equation. Common applications of potentiometry include clinical analysis of electrolytes, environmental analysis of ions in water, and titration measurements.
Potentiometry involves measuring the potential (voltage) between an indicator electrode and a reference electrode immersed in a solution. The potential measurement provides information about the concentration of an analyte in the solution. Common reference electrodes include the saturated calomel electrode (SCE) and silver-silver chloride electrode, which maintain a constant potential. pH electrodes function as indicator electrodes, with their potential directly proportional to the pH of the solution. The potential measurement is made against the reference electrode using a pH meter, which can be calibrated using buffer solutions.
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.
The potentiometer is used to accurately measure potential differences, currents, and resistances. It consists of a long uniform wire stretched parallel on a board, with terminals at both ends connected to copper strips. A battery maintains a current through the wire, forming the primary circuit. A cell's terminals connect to points on the wire in a secondary circuit including a galvanometer. The balancing length where no current flows through the galvanometer is directly proportional to the cell's electromotive force. A potentiometer can also compare emf values of two cells and determine a cell's internal resistance by varying an external resistor connected across it.
Analytical class potetiometry conductomtry, P K MANIP.K. Mani
This document discusses potentiometric and conductometric titrations. It provides details on reference electrodes like the saturated calomel electrode and silver-silver chloride electrode. It describes indicator electrodes including metallic electrodes of the first and second type that respond directly or indirectly to analyte concentration. Membrane electrodes like glass pH electrodes are also discussed. The principles of potentiometry are explained through diagrams of electrode systems and the Nernst equation. Liquid junction potentials and factors influencing reference electrode potentials are summarized.
Basics of Electrochemistry and Electrochemical MeasurementsHalavath Ramesh
A potentiostat is an electronic instrument that controls the voltage difference between a working electrode and a reference electrode by injecting current through an auxiliary electrode. It is used to apply a potential to an electrochemical cell and measure the resulting current. A potentiostat requires a three-electrode cell with a working electrode, reference electrode, and counter electrode. The working electrode is where the potential is controlled and current is measured. Common reference electrodes include the saturated calomel electrode and silver/silver chloride electrode, which maintain a constant potential. The counter electrode completes the circuit by allowing current to flow out of the cell. Potentiostats are used to study electrochemical reactions and processes.
The document discusses the band structure of electrons in solids. It explains that when electrons are placed in a periodic potential, as in metals and semiconductors, the allowed energy levels split and form bands separated by band gaps. The nearly-free electron model is introduced to account for this band structure by treating electrons as interacting with a periodic lattice potential rather than being completely free. The key outcomes are that the energy-momentum relationship becomes a series of bands rather than continuous, and band gaps open up where electron states are forbidden. This distinguishes conductors, semiconductors and insulators.
Cyclic voltammetry is an electroanalytical technique that measures current during redox reactions at an electrode. It involves scanning the potential of a working electrode versus a reference electrode and measuring the current. The potential is ramped from an initial value to a set switching potential and back to the initial value. This process is repeated in cycles. A cyclic voltammogram plots the current response of the working electrode versus the applied potential and provides information about redox potentials and reaction reversibility. Reversible reactions produce symmetrical peaks while irreversible reactions have wider separation between peaks. Cyclic voltammetry is useful for studying electrode reaction mechanisms and kinetics.
Electrochemistry class 12 ( a continuation of redox reaction of grade 11)ritik
Electrochemistry involves the study of chemical reactions that produce electricity and chemical reactions produced by electricity. A galvanic (voltaic) cell converts the chemical energy of a spontaneous redox reaction into electrical energy. Daniell's cell uses the redox reaction of zinc oxidizing copper ions to produce a cell potential of 1.1 V. An electrolytic cell uses an applied voltage to drive a nonspontaneous redox reaction in the opposite direction of the natural reaction in a galvanic cell. Standard reduction potentials allow prediction of the tendency of half-reactions to occur and their oxidizing or reducing power.
This document provides an overview of electrochemistry and discusses several key concepts:
- Electrochemistry involves using chemical reactions to produce electricity or using electricity to drive non-spontaneous reactions.
- Oxidation and reduction reactions occur at electrodes in electrochemical cells. The standard electrode potential table allows determination of reaction spontaneity.
- Daniell cells convert the chemical energy of a redox reaction into electrical energy. The cell potential is equal to the difference between the standard potentials of the cathode and anode half-reactions.
This document provides an overview of electrochemistry concepts including:
1) Galvanic (voltaic) cells which are spontaneous chemical reactions that can be used as batteries. They have an anode, cathode, salt bridge or porous disk, and electron flow from anode to cathode.
2) Electrolytic cells which are non-spontaneous and require an external electron source like a DC power supply.
3) Standard reduction potentials which indicate the tendency of elements to gain or lose electrons. More positive potentials indicate easier reduction. This can be used to determine if a reaction is spontaneous.
4) The Nernst equation relates cell potential to non-standard conditions by accounting for react
Electrochemistry is the study of chemical reactions involving the transfer of electrons. Oxidation and reduction reactions occur in electrochemical cells. Daniel cell is an example of a galvanic cell that converts chemical energy to electrical energy. It consists of zinc and copper half cells separated by a salt bridge. The cell potential depends on the standard electrode potentials of the half reactions and can be calculated using Nernst's equation. Equilibrium constants can also be determined from standard cell potentials using thermodynamic relationships.
Electrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materialsElectrical properties of materials
The document discusses kinetics of electrochemical reactions and mass transfer in electrochemical systems. It covers the following key points:
1) Chemical kinetics is the study of reaction rates and mechanisms. In industrial synthesis, reaction rates are as important as equilibrium constants. Kinetics answers how fast reactions occur, while thermodynamics addresses if they will occur.
2) Applying a potential increases the reaction rate by reducing the activation energy barrier. Current increases with increasing driving force from an applied potential. Catalysts also reduce the activation energy.
3) The rate of electrochemical reactions depends on parameters like materials, composition, and temperature. Increasing the reaction rate improves fuel cell performance. Reactions occur at electrode-elect
Electrogravimetry involves the electrolytic deposition of an element onto an electrode, which is then weighed before and after deposition to determine the amount deposited. There are two main methods - constant current electrolysis, where current is kept constant and potential varies, and constant potential electrolysis, where potential is kept constant. Electrogravimetry can be used to determine the concentration of elements in solutions and to separate elements electrolytically based on their deposition potentials. It has applications in quantitative analysis, electrosynthesis, separating species in solutions, and purifying reagents.
Potentiometry uses a reference electrode and an indicator electrode to measure the potential difference in a sample solution. When the electrodes are placed in the solution, the potential is generated based on the concentration of ions present. There are several types of potentiometric titrations including acid-base, redox, complexometric, and precipitation titrations. Potentiometry has many applications in fields like clinical chemistry, environmental analysis, potentiometric titrations, agriculture, detergent manufacturing, food processing and more. It is used to analyze important ions and determine equivalence points during titrations.
This document summarizes the key electrical properties of metals and semiconductors. It discusses Ohm's law and how electrical conductivity in metals is influenced by drift velocity and current density. It also explains how resistivity is related to temperature in metals. For semiconductors, it describes the band structure of insulators, metals and semiconductors and how conductivity varies with intrinsic carrier concentration and temperature in intrinsic semiconductors. It then discusses the effects of doping on carrier concentrations and conductivity in n-type and p-type extrinsic semiconductors. Finally, it provides an overview of compound semiconductors made of two or three elements.
This document discusses devices used in electrochemical analysis and auxiliary laboratory devices. It describes galvanic cells, electrodes, and potentiometric devices used to determine ionic composition. It also discusses auxiliary devices like centrifuges and thermostats. Conductometers and coulometers are described which measure conductivity by applying a low voltage alternating current between electrodes to avoid electrolysis. pH meters and glass electrodes are summarized which can directly measure pH by relating the electrode voltage to hydrogen ion concentration.
This document provides an overview of electrochemistry techniques used in clinical chemistry, including potentiometry, voltammetry, coulometry, and conductometry. It describes the basic concepts such as electrochemical cells and electrodes. Potentiometry techniques like ion-selective electrodes and their applications in measuring electrolytes are discussed in detail. Other techniques like amperometry and different types of voltammetry and coulometry are also summarized along with their uses and advantages.
pH and Potentiometry, Potentiometric titrations, Electrodes used in Potentiometry, Standard Hydrougen electrode, calamel electrode, silver silver chloride electrode, glass electrode
1. The document discusses experimental methods to verify the validity of the Debye-Hückel and Onsager equations, which describe electrolyte behavior at high dilutions.
2. Using liquid membrane cells, studies were able to examine dilutions as high as 10-4 M and found that the Debye-Hückel equation holds for 1:1 electrolytes but shows negative deviations for 2:2 or 3:2 electrolytes.
3. Conductance measurements of various electrolytes at different temperatures found close agreement with the Onsager equation at low concentrations, validating it as accurately describing conductance behavior at high dilutions.
This document discusses electrogravimetry, which is the quantitative analysis of substances by electrolysis. It defines key terms used in electrogravimetry like cathode, anode, current density, and overpotential. It explains Faraday's laws of electrolysis and how they relate to the amount of material deposited. It also describes how controlling variables like cathode potential can be used to selectively deposit metals and separate them from each other.
Potentiometry is an electroanalytical technique that measures the electric potential of electrochemical cells under zero-current conditions. It involves measuring the potential difference between a reference electrode with a known potential and an indicator electrode whose potential varies with the concentration of the analyte ion. The potential difference is used to determine analyte concentration based on the Nernst equation. Common applications of potentiometry include clinical analysis of electrolytes, environmental analysis of ions in water, and titration measurements.
Potentiometry involves measuring the potential (voltage) between an indicator electrode and a reference electrode immersed in a solution. The potential measurement provides information about the concentration of an analyte in the solution. Common reference electrodes include the saturated calomel electrode (SCE) and silver-silver chloride electrode, which maintain a constant potential. pH electrodes function as indicator electrodes, with their potential directly proportional to the pH of the solution. The potential measurement is made against the reference electrode using a pH meter, which can be calibrated using buffer solutions.
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.
The potentiometer is used to accurately measure potential differences, currents, and resistances. It consists of a long uniform wire stretched parallel on a board, with terminals at both ends connected to copper strips. A battery maintains a current through the wire, forming the primary circuit. A cell's terminals connect to points on the wire in a secondary circuit including a galvanometer. The balancing length where no current flows through the galvanometer is directly proportional to the cell's electromotive force. A potentiometer can also compare emf values of two cells and determine a cell's internal resistance by varying an external resistor connected across it.
Analytical class potetiometry conductomtry, P K MANIP.K. Mani
This document discusses potentiometric and conductometric titrations. It provides details on reference electrodes like the saturated calomel electrode and silver-silver chloride electrode. It describes indicator electrodes including metallic electrodes of the first and second type that respond directly or indirectly to analyte concentration. Membrane electrodes like glass pH electrodes are also discussed. The principles of potentiometry are explained through diagrams of electrode systems and the Nernst equation. Liquid junction potentials and factors influencing reference electrode potentials are summarized.
Basics of Electrochemistry and Electrochemical MeasurementsHalavath Ramesh
A potentiostat is an electronic instrument that controls the voltage difference between a working electrode and a reference electrode by injecting current through an auxiliary electrode. It is used to apply a potential to an electrochemical cell and measure the resulting current. A potentiostat requires a three-electrode cell with a working electrode, reference electrode, and counter electrode. The working electrode is where the potential is controlled and current is measured. Common reference electrodes include the saturated calomel electrode and silver/silver chloride electrode, which maintain a constant potential. The counter electrode completes the circuit by allowing current to flow out of the cell. Potentiostats are used to study electrochemical reactions and processes.
The document discusses the band structure of electrons in solids. It explains that when electrons are placed in a periodic potential, as in metals and semiconductors, the allowed energy levels split and form bands separated by band gaps. The nearly-free electron model is introduced to account for this band structure by treating electrons as interacting with a periodic lattice potential rather than being completely free. The key outcomes are that the energy-momentum relationship becomes a series of bands rather than continuous, and band gaps open up where electron states are forbidden. This distinguishes conductors, semiconductors and insulators.
Cyclic voltammetry is an electroanalytical technique that measures current during redox reactions at an electrode. It involves scanning the potential of a working electrode versus a reference electrode and measuring the current. The potential is ramped from an initial value to a set switching potential and back to the initial value. This process is repeated in cycles. A cyclic voltammogram plots the current response of the working electrode versus the applied potential and provides information about redox potentials and reaction reversibility. Reversible reactions produce symmetrical peaks while irreversible reactions have wider separation between peaks. Cyclic voltammetry is useful for studying electrode reaction mechanisms and kinetics.
Electrochemistry class 12 ( a continuation of redox reaction of grade 11)ritik
Electrochemistry involves the study of chemical reactions that produce electricity and chemical reactions produced by electricity. A galvanic (voltaic) cell converts the chemical energy of a spontaneous redox reaction into electrical energy. Daniell's cell uses the redox reaction of zinc oxidizing copper ions to produce a cell potential of 1.1 V. An electrolytic cell uses an applied voltage to drive a nonspontaneous redox reaction in the opposite direction of the natural reaction in a galvanic cell. Standard reduction potentials allow prediction of the tendency of half-reactions to occur and their oxidizing or reducing power.
This document provides an overview of electrochemistry and discusses several key concepts:
- Electrochemistry involves using chemical reactions to produce electricity or using electricity to drive non-spontaneous reactions.
- Oxidation and reduction reactions occur at electrodes in electrochemical cells. The standard electrode potential table allows determination of reaction spontaneity.
- Daniell cells convert the chemical energy of a redox reaction into electrical energy. The cell potential is equal to the difference between the standard potentials of the cathode and anode half-reactions.
This document provides an overview of electrochemistry concepts including:
1) Galvanic (voltaic) cells which are spontaneous chemical reactions that can be used as batteries. They have an anode, cathode, salt bridge or porous disk, and electron flow from anode to cathode.
2) Electrolytic cells which are non-spontaneous and require an external electron source like a DC power supply.
3) Standard reduction potentials which indicate the tendency of elements to gain or lose electrons. More positive potentials indicate easier reduction. This can be used to determine if a reaction is spontaneous.
4) The Nernst equation relates cell potential to non-standard conditions by accounting for react
Electrochemistry is the study of chemical reactions involving the transfer of electrons. Oxidation and reduction reactions occur in electrochemical cells. Daniel cell is an example of a galvanic cell that converts chemical energy to electrical energy. It consists of zinc and copper half cells separated by a salt bridge. The cell potential depends on the standard electrode potentials of the half reactions and can be calculated using Nernst's equation. Equilibrium constants can also be determined from standard cell potentials using thermodynamic relationships.
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.
Cell potential represents the driving force for electrochemical reactions. It is measured as the difference in electrical potential between the electrodes in an electrochemical cell. Cell potential depends on the standard electrode potentials of the half-reactions occurring at each electrode. If the cell potential is positive, the reaction is spontaneous and electrons will flow from the anode to the cathode. Cell potential can be calculated using the Nernst equation, which accounts for non-standard reactant and product concentrations. Common applications of cell potential include batteries and galvanic cells, which generate electrical energy from spontaneous redox reactions.
PPT on electrochemistry and energy storage systemsbk097027
This document discusses electrochemistry and energy storage systems. It defines key thermodynamic concepts like internal energy, enthalpy, entropy, and Gibbs free energy. It then explains how these concepts relate to electrochemical cells and redox reactions. Specifically, it discusses how the change in Gibbs free energy of a reaction relates to the maximum work output and cell potential. The document also covers topics like the Nernst equation, electrochemical series, and different types of reference electrodes.
This document provides an overview of the key concepts in electrochemistry including oxidation-reduction reactions, galvanic cells, standard reduction potentials, the Nernst equation, electrolysis, batteries, corrosion, and commercial electrolytic processes. It defines important terms, describes experimental set ups and calculations for electrochemical cells, and summarizes fundamental electrochemical principles and laws such as Faraday's laws of electrolysis.
This document provides an overview of key concepts in electrochemistry:
1) It defines oxidation, reduction, and redox reactions, and describes direct and indirect redox reactions.
2) It explains the components and functioning of an electrochemical cell, including the anode, cathode, salt bridge, and representation of half-cells.
3) It introduces standard electrode potential and the electrochemical series, and describes how potential is affected by concentration and temperature.
Potentiometry: Electrical potential, electrochemical cell, reference electrodes, indicator
electrodes, measurement of potential and Ph, construction and working of electrodes,
Potentiometric titrations, methods of detecting end point, Karl Fischer titration.
ppt uit 2 link -final - (1.1.23) - Copy.pptxKundanBhatkar
Electrochemistry deals with the transformation of chemical energy into electrical energy and vice versa. An electrochemical cell converts this energy and can be classified as either galvanic/voltaic, which converts chemical to electrical, or electrolytic, which converts electrical to chemical. The Nernst equation describes the relationship between cell potential and reaction conditions. Electrodes can be reference electrodes, which have a stable and reproducible potential, or indicator electrodes, which respond to specific ions. Common reference electrodes include calomel and silver-silver chloride, while common indicator electrodes include glass and ion-selective electrodes.
ELECTROCHEMISTRY - I
4.1 - Metallic and Electrolytic Conductors-Faraday’s Laws-Electro plating Specific conductance and Equivalent conductance - Measurement of equivalent conductance - Variation of Equivalent Conductance and Specific Conductance with Dilution Kohlrausch Law and its applications - Ostwald’s Dilution Law and its Limitations.
This document discusses electrochemistry and electrochemical cells. It defines electrochemistry as the study of chemical reactions that produce electricity or use electricity to cause reactions. There are two types of electrochemical cells: galvanic cells that convert chemical energy to electrical energy, and electrolytic cells that use electrical energy to drive non-spontaneous reactions. Examples of galvanic cells include Daniell cells and concentration cells. The document explains concepts like standard electrode potentials, the electrochemical series, and how to represent cell diagrams according to IUPAC recommendations. It also discusses the functions of salt bridges and how junction potentials can affect cell potentials.
Electrochemistry deals with chemical reactions caused by electric currents or electric currents produced by chemical reactions. Galvanic cells convert chemical energy to electrical energy through redox reactions. Reversible cells like Daniel cells can undergo reactions in both directions while irreversible cells like zinc-silver cells cannot. Protective metal coatings through electroplating or electroless plating prevent corrosion by depositing a noble metal layer on a substrate.
This document discusses the principles of potentiometric measurement. Potentiometry involves measuring the potential of an electrochemical cell under conditions of zero current flow, allowing the cell composition to remain unchanged. The potential is related to analyte concentration by the Nernst equation. Potentiometric cells consist of a sensing electrode and a reference electrode separated by a salt bridge. The potential difference between the electrodes corresponds to analyte levels. Common sensing electrodes include ion-selective electrodes and metallic electrodes like silver or copper that respond to specific ions.
CBSE Class 12 Chemistry Chapter 3 (Electrochemistry) | Homi InstituteHomi Institute
1. Electrochemistry is the study of chemical processes involving the movement of electrons, which can generate electricity through oxidation-reduction reactions.
2. A salt bridge is a device used in electrochemical cells to connect the half cells and maintain electrical neutrality, preventing the accumulation of charges that would stop the reaction.
3. Common reference electrodes include the standard hydrogen electrode and silver-silver chloride electrode, but the standard hydrogen electrode is difficult to assemble and maintain precisely.
Voltaic cells harness energy from chemical reactions through redox processes. An electrochemical cell consists of two half-cells where oxidation and reduction occur separately. A voltaic cell specifically converts chemical energy to electrical energy via a spontaneous redox reaction. The standard cell potential, which determines if a reaction is spontaneous, can be calculated from the standard reduction potentials of each half-cell reaction.
Electrochemistry is the study of chemical reactions that produce electricity and electrical energy's ability to cause non-spontaneous reactions. There are two types of electrochemical cells: galvanic cells that convert chemical energy to electrical energy, and electrolytic cells that use electrical energy to drive non-spontaneous reactions. Galvanic cells contain a spontaneous redox reaction like in Daniel cells where zinc oxidizes and copper reduces. Electrolytic cells use an external voltage to force nonspontaneous redox reactions. Standard electrode potentials allow prediction of reaction spontaneity based on the cell potential relative to the standard hydrogen electrode.
This document provides an overview of electrochemical energy sources and fuel cells. It discusses the concepts of electrochemistry including electrical conduction, measurement of conductance, and types of electrochemical cells. It describes galvanic cells and how they generate electrical energy from chemical reactions. It also covers different types of batteries including primary batteries like dry cells and secondary rechargeable batteries like lead-acid and nickel-cadmium cells. Finally, it provides details on the working principles of hydrogen fuel cells and their use in generating electricity.
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2. Measurements of electrode potential
• We can always measure the electrode
potential for an electrode in combination with
standard electrode which is standard
hydrogen electrode (SHE)
• It was conventionally agreed that electrode
potential for hydrogen is zero.
4. Cont..
• When electrode potential of any element is
measured against hydrogen electrode at ,1
atm and 1M concentration is called standard
electrode potential.
• That is, if the electrode potential is measured
under standard conditions (1M solution, 1atm
pressure, ) relative to standard hydrogen
electrode it is a standard electrode potential.
6. • Salt Bridge Is an inverted U-tube that contains
electrolyte (e.g. ) which connects the
solution of two half cells to balance the charge
and to complete the circuit.
• NOTE :
The standard redox potential is actually
reduction potential. All elements below
hydrogen have negative reduction potential
and positive oxidation potential hence strong
reducing agents.
• All elements above hydrogen have positive
reduction potential and negative oxidation
potential hence strong oxidizing agents.
7. • Consider the following arrangements for
determine electrode potential for:
I. Zinc.
=
The zinc electrode is negative.
• Cell reaction:
8. II. Copper
The copper electrode is positive. (It can easily
be reduced)
• Cell reaction:
• Overall:
9. Application of standard electrode potential
I. Construction of electrochemical cells.
II. Prediction of occurrence of chemical reaction
III. Determination of pH a solution without pH
meter
IV. Replacement of elements in the
electrochemical series.
V. Determination of equilibrium constant.
VI. Determination of concentration of ions.
10. CONSTRUCTION OF ELECTROCHEMICAL
CELLS
• Electrochemical cells are devices that use chemical
reactions to produce electrical power.
• These are sometimes known as Galvanic or Voltaic
cells. e.g. dry cells, car batteries.
• It contains two half cells connected together by
external circuits.
• Half cell is an arrangement which consists of an
electrode dipped into a solution containing its ions.
• When the two half cells are connected, the resulting
component is called electrochemical cell. A good
example is Daniel cell. It is constructed from Zinc and
copper electrode.
11. Procedure for construction of
electrochemical cell
1. Identify between the electrodes, which electrode is
supplying or gaining electrons by studying their electrode
potential.
II. An electrode with negative standard electrode potential is
more reactive (supplies electrodes) than the positive one.
• If both are negative the one which has more negative
electrode potential is more reactive.
E.g. Sn = -0.16
Mg = -0.25 (more reactive)
• If both electrodes are positive, the one which has less
positive value is more reactive.
E.g. 0.07v (more reactive)
0.2v
12. • The electrode which supplies electrons should
be placed on the left and electrode which
gains electrons should be on the right hand
side.
• E.g. construct a Daniel cell and shows the
direction of flow of electrons and current
given that
•
13.
14. • The electrode which supplies electrons oxidation takes
place and the electrode is oxidized.
• This electrode is called ANODE.
• The electrode which receives electrons reduction takes
place and the electrode is REDUCED.
• It is called CATHODE.
Zn – anode
Cu – cathode
• Overall reaction is obtained by adding the two half
reactions and is called cell reaction.
Anodic reaction:
Cathodic reaction:
Cell reaction:
15. • Electrochemical cell can also be represented in
an abbreviation way known as cell notation.
Anode cathode
I.e. for Daniel cell
16. Examples …
• Given the overall reactions, write their
corresponding cell notations
a)
• From the cell notation give the cell reactions
a)
17. ELECTROMOTIVE (EMF) FORCE OF A CELL
• The difference between electrode potential of
the two electrodes constituting an
electrochemical cell is known as electromotive
force (emf) or cell potential.
• This acts as a driving force for a cell reaction
and it is expressed in volts.
• The emf of a cell is calculated by subtracting
the standard electrode potential of the left
electrode from that of the right electrode.
18. • For Daniel cell :
= 0.34 – (-0.76)
= 1.1v
Note: in applying this formulae of calculation of
cell potential, make sure only reduction
potentials are used and not otherwise.
19. Prediction of the occurrence of
chemical reaction….
• If the emf of the cell calculated is negative the
reaction is non spontaneous i.e. the reaction
does not occur in the way it is written unless
external forces apply but the reaction is
spontaneous in the opposite direction.
• If the emf of the cell is positive the reaction is
spontaneous
20. • Example: given the following reaction
• Predict the direction of the reaction given that
reduction potential of nickel (Ni2+/Ni) Eo = -0.25v
of mercury Hg+/Hg = 0.14v
Solution:
Cell notation:
• The reaction is non spontaneous since emf is
negative hence backward reaction is favored.
21. Example 2…
• Briefly explain what happen when
I.Fe is dipped in CuSO4 solution
II.Cu is dipped in FeSO4 solution
22. (i) since Fe has a negative reduction potential
then it has a positive oxidation potential and
hence will displace copper metal from CuSO4
solution
(ii)Since Cu has positive reduction potential,
then it has a negative oxidation potential and
hence it will NOTE displace Fe from
FeSO4solution therefore no reaction will be
possible.
23. EFFECTS OF CONCENTRATION AND
TEMPERATURE ON CELL POTENTIALS
• We have been considering electrode potential
under standard conditions of molar solution,
pressure of 1 atom and 298K.
• When the conditions are altered the values of
electrode potential changes thus we have to
define the potential of the cell under non-
standard conditions.
• The Nernst equation shows the relationship
between emf of the cell at standard conditions
and emf under non-standard conditions.
24. • R – Universal gas constant (8.314 Jmol-1K-1)
• n – Number of moles electrons being
transferred
• F – Faraday’s constant (96500c)
• At standard temperature (298K)
25. • OR
• The above equation can be applied to half
reactions and overall reactions
NOTE
Always write a balanced cell reaction to obtain
‘n’ and position of ions, either reactants or
products together with their stoichiometry.
30. Concentration cell….
• If two plates of the same metal are dipped
separately into two solutions of the same
electrolytes at different concentration and the
solution are connected with a salt bridge, the
whole arrangement is found to act as a
galvanic (electrochemical) cell.. Why??
• This is because at different concentration of
the electrolyte, the two half cells have
different electrode potential.
31. • The plate with more dilute solution has a
lower electrode potential and hence it acts as
an anode (the –ve electrode)
• The plate with more concentrated solution
has a higher electrode potential and hence it
acts as a cathode (the +ve electrode)
34. Measurement of ph of a solution using
standard electrode potential.
• pH is the degree of alkalinity, or acidity of a
substance. It is obtained by using the hydrogen
ion concentration pH = -
• The pH of a solution is determined by using any
electrode provided its standard electrode
potential is known and the concentration of ions
in that electrode should be 1M. This will be one
of the half cells another half cell is made up
hydrogen electrode dipped into the solution
whose pH is to be determined
37. Applying Nernst equation at standard
temperature
E cell = cell –
= 0.8 –
E cell= 0.8 + 2 (
E cell = 0.8 + 0.0591
pH= =
38. Question…….
Calculate the of the following cell and
hydrogen ion concentration.
Zn/Zn2+ // H+ /H2, pt
Zn2+ /Zn = -0.76v
E cell = 0.115v
39. EQUILIBRIUM CONSTANT OF
GALVANIC CELL
• Consider to what happens to a Daniel’s cell if we use it
to do some electrical work i.e. it can be connected to a
small electric motor.
• After sometimes the motor will stop. The cell will run
down.
• When this happens then there is no overall transfer of
electricity from one half cells to the other. When there
is no overall change taking place in a chemical reaction
the equilibrium has been established.
• At equilibrium, electron density of both electrodes is
equal and there is no transfer of electricity between
the two half cells.
40. Applying the Nernst equation to a
Daniel’s cell
Since the reaction is at equilibrium, the ratio
• KC = 1.67 x 1037
41. • The large value tells us that, the equilibrium
lies almost entirely in favour of copper metal
and zinc ions.
• Generally, the cell at equilibrium at standard
temperature is given by the following
expression;
43. ELECTROCHEMICAL SERIES
• Is the series of standard electrode potential
with respect to their elements from more
negative standard electrode potential to the
more positive standard electrode potential.
• Is the arrangement of electrodes of elements
in order of reducing power
44. Uses….
1. It is a good guide for predicting reaction that
takes place in solution especially
displacement reaction.
• Displacement reaction
– Is a types of reaction in which an atom or element
displace another element or atom in a compound
• Therefore, the electrochemical series can be
used to determine which element will displace
which element in the displacement reaction.
45. Uses…
2. Displacement of hydrogen from mineral
acids
Metals which are higher in the electrochemical
series than hydrogen reacts with acids and
replaces hydrogen but metals below hydrogen
have no action with mineral acids.
Complete the following reaction:-
i. Zn(s) + 2HCl (aq) ZnCl2(s) + H2(g)
ii. Cu(s) + HCl(aq) No reaction
46. Uses…
3. The knowledge of electrochemical series helps as
on choosing method for extraction of metals.
Example
Higher most metal can’t be extracted from the oxides by
chemical reduction process. This is because they are
strong reducing agent hence they can be reduced
easily from their oxide by electrolysis.
47. • Question.
For electrolysis, fused or molten metal should be
used and not aqueous solution. Why?
Answer:-
In aqueous solution, there are H+ ions. Hence
metals prefer to react with element in lower
electrochemical series than the metal itself,
hence for electrolysis we use fused or molten
metal and not aqueous solution.
48. CORROSION AND ITS PREVENTION
• Corrosion is the deterioration of the metals
due to the chemical reactions taking place on
the surface. Usually, the process is due to the
loss of metal to a solution in some forms by a
redox reaction (unwanted redox reactions)
49. • For corrosion to occur on the surface of a metal
there must be anodic area where a metal can be
oxidized to metal ions as electrons are produced.
Anode area:-
M (s) Mn+ + ne+
And cathodes area where electrons are
consumed by any of all of several half reactions.
Cathodic reaction:-
2H+
(aq) + 2e- H2 (g)
2H2 O(l) + 2e- 2OH-
(aq)+ H 2(g)
4e- + O2(g) +H2 O(l) 4OH-
(aq)
• Anodic reactions occur at cracks or around the
area with some impurities.
50. RUSTING OF IRON
• The most common corrosion process is rusting of iron
• Rust is hydrated iron (III) Oxide (Fe2O3. XH2O) which
appears as a reddish brown substance on the surface of
the iron bar.
• Both water and air (oxygen) are required for rusting
to occur.
• The presence of dissolved salts and acid in water
increases its conductivity and speed up the process of
rusting.
• If the iron object has free access to oxygen and H2O as
in flowing water, a reddish brown ion (III) oxide will be
formed which is a rust.
53. • If oxygen is not freely available: The farther
oxidation of iron (II) hydroxide is limited to
formation of magnetic iron oxide.
•
• 6Fe(OH)2(s) + O2(g) 2Fe3 O3.H2O + 4H2O(l)
• Fe3O4 + H2O(l) Fe3O4 + 4H2O
Black magnetite
54. Electrolytes…
• These are substances which allow electricity to pass through them
in their molten state or in form of their aqueous solution, and
undergo chemical decomposition e.g., acids, bases and salts.
Classification of electrolytes
All electrolytes do not ionize by the same extent in the solution.
According to this we have strong and weak electrolytes
Strong electrolytes are those that ionize completely into ions in the
solution
e.g. Salts, mineral acids, some bases.
Weak electrolytes are these that ionize partially into ions in the solution
e.g. in organic acids. HCN, Na4OH.
55. Electrolytic conduction,
• When a voltage is applied to the electrodes dipped into
an electrolytic solution, ions of the electrolyte move
towards their respective electrodes and therefore
electric current flows through the electrolytic cell. The
process of the electrolyte to conduct electric current is
termed as conductance or conductivity.
• Like metallic conductors, electrolytic solution also obey
ohm's law which states that “the strength of the
current flowing through a conductor is directly
proportional to the potential difference applied across
the conductor and inversely proportional to the
resistance of the conductor
i.e. V = RI.
57. • Conductance is the measure of the ease with
which the current flows through a conductor a
(λ orΛ)
Conductance is the reciprocal of electric
resistance. ( )
• From the above expression high resistance
means low conductance and vice versa.
• Conductivity is the reciprocal of resistivity and
is also called specific resistance (kappa)
• = (
58. • For an electrolytic cell, l is the distance apart
between the two electrodes and A is the total
area of cross-section of the two electrodes.
Therefore, for a given cell, l and A are
constant. If the dimensions of the cell are not
altered, the ration is referred as cell
constant (K)
59. = K
R = ρ =
= , = =
=
• Molar conductance (λm)
Is the conductivity of volume of a solution
which contains 1 mole of the solute.
Or
It is the conducting power of the ions produced
by dissolving 1 mole of an electrolyte in a
solution.
60. • Molar conductance is given by where
v = volume containing 1 mole of a solute and
is called dilution.
Concentration of an electrolyte depends on
the volume i.e.
V =
=
• Where C is the concentration in mol/dm3
and is m-1
61. VARIATION OF MOLAR CONDUCTIVITY WITH
CONCENTRATION
• The intensity of electricity that can pass through the
solution depends on
i.The number of concentration of free ions present
in the solution.
ii. Speed with which ions move to their respective
electrodes.
• An increase in concentration gives an increase in total
number of solute particles in a given volume of
solution and this might well be expected to give an
increased conductivity.
• Conduction in strong electrolytes.
62. • The molar conductivity is high since strong
electrolytes ionize completely into free ions and
the molar conductivity increases slightly in
dilution. WHY?
• In strong electrolytes, there are vast numbers of
ions which are close to each other. These ions
tend to interfere with each other as they move
towards their respective electrodes. The positive
ion are held back by the negative ions and vice
versa which in turn interrupts their movement to
the electrodes (reduce the speed with which they
move)
• Dilution ions get separated from each other and
at an average distance they can move freely or
easily.
63. • NOTE:-
• As the dilution increases, there comes a time
for amount of interference become small so
that further dilution to has no effect.
• At this point the molar conductivity remains
constant and it is known as molar conductivity
at zero concentration .
64. Conduction in weak electrolyte..
• The molar conductivity is less because there is
less number of particles as the minority of
particles are dissociated into ions. On dilution
the molar conductivity increases as the
molecules dissociate more into ions which
increases the number of free ions. Therefore
for weak electrolytes the molar conductivity
depends on the degree of dissociation of
molecules into ions.
65.
66. MOLAR CONDUCTIVITY AND DEGREE
OF DISSOCIATION
• The molar conductivity of weak electrolyte is proportional to the
degree of dissociation.
i.e.
= K ................ (i)
• At infinity dilution, the weak electrolyte is completely ionized.
= 1 or 100%
= K (Constant)........... (ii)
Taking ratio of equation (i) and (ii)
67. Ostwald's dilution law
• It states that
• “For a weak electrolyte the degree of
dissociation is proportional to the square root
of reciprocal of concentration”
• Consider a weak binary electrolyte AB (i.e.
ethanoic acid) in solution with concentration C
(mol/ ).
68. AB A+
(aq) + B-
(aq)
1mole 0 0 start
At equilibrium
But V =
AB A+
(aq) + B-
(aq)
K =
But AB = CH3 COOH
=
69. • For a weak electrolyte, degree of dissociation
is very small thus the expression
1- 1
Ka=
K a = C
70. Example…
• 1. At 250c the solution of O.1M of ethanoic acid
has a conductivity of 5.0791x10-2 m-1mol-1.
calculate the pH of the solution and dissociation
constant Ka (Answer Ka=1.69 10-2M)
• 2. A 0.001 moldm-3 solution of ethanoic acid was
found to have molar conductivity of
14.35Sm2mol-1. Use this value together with
molar conductivity at infinity dilution of ethanoic
acid (C ) is 390.7Ð… to calculate :-
i. Calculate degree of dissociation of acid
ii. Equilibrium constant