This document provides an overview of potentiometry and related electroanalytical techniques. It defines key concepts like reference electrodes, indicator electrodes, and salt bridges used in potentiometric cells. Equations for electrode potentials are described for various metal-metal ion systems. Membrane electrodes like glass pH electrodes are also summarized. The document concludes with brief discussions of potentiometric titration techniques and voltammetry methods.
This document discusses amperometric titration, which is an electrochemical titration method that measures current under a constant applied voltage. It explains the principle that the current passing through an indicator electrode is measured during titration as the concentration of electroreducible ions changes. The document outlines the conditions, apparatus used including dropping mercury and rotating platinum microelectrodes, types of amperometric titrations, advantages such as ability to analyze reducible and non-reducible ions, applications including HPLC detection, and disadvantages like inaccurate results from foreign substances.
ESTIMATION OF THE RATE OF REACTION WILL BE DONE BASED ON THE POTENTIAL DIFFERENCE BETWEEN REFERENCE AND INDICATOR ELECTRODE. THE POTENTIAL OF THE REFERENCE ELECTRODE IS STABLE WHERE AS THE POTENTIAL OF THE INDICATOR ELECTRODE VARIES WITH THE POTENTIAL OF THE SOLUTION IN WHICH IT IS PLACED
Potentiometry is an electroanalytical technique where the potential difference between two electrodes is measured under conditions of no current flow. It was invented in 1841 by Johann Christian Poggendorff using a slide-wire potentiometer. A potentiometric cell consists of a reference electrode with a known potential and an indicator electrode, whose potential changes depending on the analyte concentration. The potential difference between the electrodes is measured to determine the analyte concentration. Common applications of potentiometry include titrations, analysis of pollutants, drugs, foods, and more.
This document provides an overview of coulometry, which is an electroanalytical technique used for quantitative analysis. There are two forms of coulometry: controlled-potential coulometry and controlled-current coulometry. Both techniques involve completely oxidizing or reducing an analyte and measuring the total charge passed to determine the amount of analyte. Controlled-potential coulometry applies a constant potential while controlled-current coulometry applies a constant current. Factors like electrolysis time, electrode area, and stirring rate affect the analysis. Coulometry is used to quantify both inorganic and organic analytes.
It contains what is amperometry and where it will be derived and what is the principle behind the amperometry. Instrumentation of amperometry and the purpose of dipping mercury electrode and rotating platinum electrode. The advantage over rotating platinum electrodes. Amperometric titration curves for reducible ions and non-reducible ions. What tells the Ilkovic equation and how it relates to the amperometry is also included. Applications, advantages, and disadvantages of amperometric titration are also included. Questions related to amperometry and amperometric titration are given for practice. The contents taken from the websites are also given.
This document provides information on potentiometry and potentiometric titration. It discusses the basic principles of potentiometry including electrode potentials and how a potential difference is established between an electrode and solution. It describes the instrumentation used including reference electrodes like calomel and silver-silver chloride electrodes and indicator electrodes like metal, glass membrane, and quinhydrone electrodes. It also discusses different types of potentiometric titrations and provides examples of applications for potentiometry in various industries.
Potentiometry involves measuring the potential or electromotive force of a sample solution using an electrochemical cell containing a reference electrode and an indicator electrode. The potential is directly proportional to the ion concentration in the solution. Common reference electrodes include the standard hydrogen electrode, silver chloride electrode, and saturated calomel electrode. Indicator electrodes can be metal electrodes or ion-selective electrodes like the glass membrane pH electrode. Potentiometric titration determines the concentration of an analyte by measuring the potential change as a titrant is added, with the endpoint indicated by an abrupt potential shift. Applications of potentiometry include acid-base, redox, complexometric, and precipitation titrations.
This document discusses amperometric titration, which is an electrochemical titration method that measures current under a constant applied voltage. It explains the principle that the current passing through an indicator electrode is measured during titration as the concentration of electroreducible ions changes. The document outlines the conditions, apparatus used including dropping mercury and rotating platinum microelectrodes, types of amperometric titrations, advantages such as ability to analyze reducible and non-reducible ions, applications including HPLC detection, and disadvantages like inaccurate results from foreign substances.
ESTIMATION OF THE RATE OF REACTION WILL BE DONE BASED ON THE POTENTIAL DIFFERENCE BETWEEN REFERENCE AND INDICATOR ELECTRODE. THE POTENTIAL OF THE REFERENCE ELECTRODE IS STABLE WHERE AS THE POTENTIAL OF THE INDICATOR ELECTRODE VARIES WITH THE POTENTIAL OF THE SOLUTION IN WHICH IT IS PLACED
Potentiometry is an electroanalytical technique where the potential difference between two electrodes is measured under conditions of no current flow. It was invented in 1841 by Johann Christian Poggendorff using a slide-wire potentiometer. A potentiometric cell consists of a reference electrode with a known potential and an indicator electrode, whose potential changes depending on the analyte concentration. The potential difference between the electrodes is measured to determine the analyte concentration. Common applications of potentiometry include titrations, analysis of pollutants, drugs, foods, and more.
This document provides an overview of coulometry, which is an electroanalytical technique used for quantitative analysis. There are two forms of coulometry: controlled-potential coulometry and controlled-current coulometry. Both techniques involve completely oxidizing or reducing an analyte and measuring the total charge passed to determine the amount of analyte. Controlled-potential coulometry applies a constant potential while controlled-current coulometry applies a constant current. Factors like electrolysis time, electrode area, and stirring rate affect the analysis. Coulometry is used to quantify both inorganic and organic analytes.
It contains what is amperometry and where it will be derived and what is the principle behind the amperometry. Instrumentation of amperometry and the purpose of dipping mercury electrode and rotating platinum electrode. The advantage over rotating platinum electrodes. Amperometric titration curves for reducible ions and non-reducible ions. What tells the Ilkovic equation and how it relates to the amperometry is also included. Applications, advantages, and disadvantages of amperometric titration are also included. Questions related to amperometry and amperometric titration are given for practice. The contents taken from the websites are also given.
This document provides information on potentiometry and potentiometric titration. It discusses the basic principles of potentiometry including electrode potentials and how a potential difference is established between an electrode and solution. It describes the instrumentation used including reference electrodes like calomel and silver-silver chloride electrodes and indicator electrodes like metal, glass membrane, and quinhydrone electrodes. It also discusses different types of potentiometric titrations and provides examples of applications for potentiometry in various industries.
Potentiometry involves measuring the potential or electromotive force of a sample solution using an electrochemical cell containing a reference electrode and an indicator electrode. The potential is directly proportional to the ion concentration in the solution. Common reference electrodes include the standard hydrogen electrode, silver chloride electrode, and saturated calomel electrode. Indicator electrodes can be metal electrodes or ion-selective electrodes like the glass membrane pH electrode. Potentiometric titration determines the concentration of an analyte by measuring the potential change as a titrant is added, with the endpoint indicated by an abrupt potential shift. Applications of potentiometry include acid-base, redox, complexometric, and precipitation titrations.
Potentiometry is a method of analysis that determines the concentration of an ion or substance by measuring the potential developed at a sensitive indicator electrode immersed in the solution. There are two main types of indicator electrodes: metallic electrodes where redox reactions occur on the surface, and membrane electrodes where charge exchange occurs across a selective surface. Reference electrodes such as silver/silver chloride are used along with indicator electrodes to complete the circuit and allow measurement of potential. Potentiometry can be used for direct concentration measurements or titration applications such as acid-base, precipitation, complexation, and redox reactions.
This document discusses polarography, which is a technique for analyzing solutions using two electrodes - a dropping mercury working electrode and a reference electrode. It provides details on:
1. How polarography works by applying a voltage to induce a redox reaction and measuring the resulting current.
2. The components needed, including the dropping mercury electrode, reference electrode, and a supporting electrolyte.
3. How polarograms are generated by plotting current vs. applied voltage and the different regions that can be seen on a polarogram.
4. Factors that influence the diffusion current measured, such as concentration of the analyte, diffusion coefficient, and drop lifetime. Equations for calculating diffusion current are also presented.
Potentiometry involves measuring electrode potentials using a reference electrode and indicator electrode. The reference electrode maintains a constant potential while the indicator electrode's potential varies with analyte concentration. Common reference electrodes include the saturated calomel electrode and silver-silver chloride electrode. Indicator electrodes include pH electrodes, ion-selective electrodes, and redox electrodes. Potentiometric measurements are used in clinical chemistry, environmental monitoring, titrations, and various industrial applications like food processing.
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.
This document discusses potentiometry and ion selective electrodes. It begins by explaining that potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. An ion selective electrode uses a selective membrane to measure the concentration of specific ions based on the potential difference between an indicator and reference electrode. The document then describes different types of reference electrodes, indicator electrodes, and ion selective electrodes like glass membrane, solid state, liquid membrane and gas sensing electrodes. It concludes by discussing applications in clinical chemistry, environmental analysis and food processing and advantages like speed and low cost and limitations like precision and interference issues.
It is an electrochemical method of analysis used for the determination or measurement of the electrical conductance of an electrolyte solution by means of a conductometer.
Electric conductivity of an electrolyte solution depends on :
Type of ions (cations, anions, singly or doubly charged
Concentration of ions
Temperature
Mobility of ions
The main principle involved in this method is that the movement of the ions creates the electrical conductivity. The movement of the ions is mainly depended on the concentration of the ions.
The electric conductance in accordance with ohms law which states that the strength of current (i) passing through conductor is directly proportional to potential difference & inversely to resistance.
i =V/R
This document discusses potentiometry, which is a method of measuring electrical potential or electromotive force (emf) of a solution using indicator and reference electrodes. It describes the components of a potentiometric cell including the reference electrode, salt bridge, analyte solution, and indicator electrode. Various types of reference electrodes like standard hydrogen, saturated calomel, and silver/silver chloride electrodes are explained. The document also covers different types of indicator electrodes like metallic electrodes, membrane electrodes, and gas sensing probes. Direct potentiometry and potentiometric titration techniques are briefly mentioned.
Potentiometry involves measuring the potential of electrochemical cells under conditions of no current flow. There are two types - direct potentiometry measures the potential of indicator electrodes related to analyte concentration, while indirect potentiometry involves measuring potential changes during titrations. A potentiometric cell consists of a reference electrode that maintains a constant potential, an indicator electrode whose potential varies with analyte concentration, and a salt bridge. The Nernst equation describes the relationship between electrode potential and analyte concentration or activity.
Polarographic analysis is a voltammetry technique that uses a dropping mercury electrode (DME) or static mercury drop electrode (SMDE) to measure the current resulting from the electrolysis of electroactive species at controlled potentials. It involves applying a potential between a mercury working electrode and a reference electrode, like a saturated calomel electrode, while measuring the current. The current-voltage curve, or polarogram, reveals information about the species present in solution, including qualitative and quantitative analysis through measurements of diffusion current and half-wave potential. Polarography takes advantage of mercury's wide cathodic potential range and its ability to renew its surface between drops.
This document discusses potentiometric analysis and its applications. Potentiometry involves measuring the potential difference between electrodes placed in a sample solution as the concentration of ions changes, such as during acid-base, redox, complexometric, and precipitation titrations. Some key applications of potentiometry include determining electrolyte levels in clinical samples, analyzing ions in environmental samples like water, and measuring properties in various industries like food processing, detergent manufacturing, and agriculture.
Polarography uses a dropping mercury electrode (DME) to measure the current flowing through an electrochemical cell as a function of the applied potential. A polarogram plots this current versus potential and provides qualitative and quantitative information about species undergoing oxidation or reduction reactions. Jaroslav Heyrovsky invented the polarographic method in 1922 and won the Nobel Prize for his contributions to electroanalytical chemistry. All modern voltammetric methods originate from polarography. The DME provides advantages like a reproducible surface area and the ability to form amalgams with metal ions.
This document discusses potentiometry, which is an electroanalytical technique that measures the potential (voltage) of electrochemical cells containing indicator and reference electrodes. It involves using electrodes to measure voltages generated from chemical reactions. Various types of electrodes are described including metal, ion-selective, glass membrane, liquid membrane, and crystalline membrane electrodes. Applications of potentiometry include ion concentration measurements, pH measurements, and potentiometric titrations.
This document discusses potentiometry, which involves measuring the potential or emf of a solution using an indicator electrode that responds to changes in potential or pH and a reference electrode with a stable, known potential. It describes common reference electrodes like the hydrogen, saturated calomel, and silver-silver chloride electrodes. It also discusses indicator electrodes like the glass and antimony electrodes and ion-selective electrodes. Potentiometric titrations can be used to determine endpoints by measuring potential changes during titration.
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.
Amperometry refers to the measurement of current under a constant applied voltage and under these conditions it is the concentration of analyte which determine the magnitude of current.
In Amperometric titrations, the potential applied between the indicator electrode (dropping mercury electrode) and the appropriate depolarizing reference electrode (saturated calomel electrode) is kept constant and current through the electrolytic cell is then measured on the addition of each increment of titrating solution. It is a form of quantitative analysis.
Otherwise called as Polarographic or polarometric titrations.
Polarography is an electroanalytical technique that measures the current between two electrodes in a solution. It can be used for both qualitative and quantitative analysis. The document discusses the principle, instrumentation, types of currents, and applications of polarography. Polarography involves applying a voltage to a dropping mercury electrode and reference electrode in an electrolyte solution and measuring the resulting current, which provides information about electroactive species in the solution.
Polarography is an electroanalytical technique that uses a dropping mercury electrode (DME) and measures the current between two electrodes when a gradually increasing voltage is applied. The current-voltage curve obtained is used to determine analyte concentration from the diffusion current and identify species from the characteristic half-wave potential. The Ilkovic equation relates diffusion current to analyte properties like concentration, number of electrons involved, and diffusion coefficient. Polarography finds applications in qualitative and quantitative analysis of metals, drugs, and organic compounds.
Potentiometry is an analytical technique that measures the potential of electrochemical cells without drawing current. It involves using a reference electrode with a known potential and an indicator electrode whose potential varies with analyte concentration. The cell potential is measured and related to concentration using the Nernst equation. Common reference electrodes include the standard hydrogen electrode and saturated calomel electrode. Glass membrane and ion-selective electrodes are often used as indicator electrodes to detect specific ions like hydrogen or fluoride ions. Potentiometry finds applications in clinical analysis, environmental monitoring, and titration experiments.
Potentiometry involves measuring the potential difference between two electrodes under equilibrium conditions. There are two main types of electrodes - reference electrodes that maintain a constant potential, and indicator or working electrodes whose potential varies with ion concentration. Common reference electrodes include the standard hydrogen electrode, saturated calomel electrode, and silver/silver chloride electrode. Indicator electrodes include glass membrane electrodes for measuring pH and ion-selective electrodes that respond selectively to specific ions. Potentiometry is used for pH measurements, ion-selective measurements, and potentiometric titrations.
This document provides an overview of electrochemistry and electrochemical cells. It defines electrochemistry as the study of the relationship between chemical transformations and electrical energy. It describes the two main types of electrochemical cells - electrolytic cells, which convert electrical to chemical energy, and galvanic/voltaic cells, which convert chemical to electrical energy. Key aspects of electrochemical cells covered include the electrodes, electrode charges, redox reactions, cell notation, salt bridges, cell potential, and reference electrodes. The document also discusses indicator electrodes, such as glass pH electrodes and potentiometric titration methods.
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.
Potentiometry is a method of analysis that determines the concentration of an ion or substance by measuring the potential developed at a sensitive indicator electrode immersed in the solution. There are two main types of indicator electrodes: metallic electrodes where redox reactions occur on the surface, and membrane electrodes where charge exchange occurs across a selective surface. Reference electrodes such as silver/silver chloride are used along with indicator electrodes to complete the circuit and allow measurement of potential. Potentiometry can be used for direct concentration measurements or titration applications such as acid-base, precipitation, complexation, and redox reactions.
This document discusses polarography, which is a technique for analyzing solutions using two electrodes - a dropping mercury working electrode and a reference electrode. It provides details on:
1. How polarography works by applying a voltage to induce a redox reaction and measuring the resulting current.
2. The components needed, including the dropping mercury electrode, reference electrode, and a supporting electrolyte.
3. How polarograms are generated by plotting current vs. applied voltage and the different regions that can be seen on a polarogram.
4. Factors that influence the diffusion current measured, such as concentration of the analyte, diffusion coefficient, and drop lifetime. Equations for calculating diffusion current are also presented.
Potentiometry involves measuring electrode potentials using a reference electrode and indicator electrode. The reference electrode maintains a constant potential while the indicator electrode's potential varies with analyte concentration. Common reference electrodes include the saturated calomel electrode and silver-silver chloride electrode. Indicator electrodes include pH electrodes, ion-selective electrodes, and redox electrodes. Potentiometric measurements are used in clinical chemistry, environmental monitoring, titrations, and various industrial applications like food processing.
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.
This document discusses potentiometry and ion selective electrodes. It begins by explaining that potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. An ion selective electrode uses a selective membrane to measure the concentration of specific ions based on the potential difference between an indicator and reference electrode. The document then describes different types of reference electrodes, indicator electrodes, and ion selective electrodes like glass membrane, solid state, liquid membrane and gas sensing electrodes. It concludes by discussing applications in clinical chemistry, environmental analysis and food processing and advantages like speed and low cost and limitations like precision and interference issues.
It is an electrochemical method of analysis used for the determination or measurement of the electrical conductance of an electrolyte solution by means of a conductometer.
Electric conductivity of an electrolyte solution depends on :
Type of ions (cations, anions, singly or doubly charged
Concentration of ions
Temperature
Mobility of ions
The main principle involved in this method is that the movement of the ions creates the electrical conductivity. The movement of the ions is mainly depended on the concentration of the ions.
The electric conductance in accordance with ohms law which states that the strength of current (i) passing through conductor is directly proportional to potential difference & inversely to resistance.
i =V/R
This document discusses potentiometry, which is a method of measuring electrical potential or electromotive force (emf) of a solution using indicator and reference electrodes. It describes the components of a potentiometric cell including the reference electrode, salt bridge, analyte solution, and indicator electrode. Various types of reference electrodes like standard hydrogen, saturated calomel, and silver/silver chloride electrodes are explained. The document also covers different types of indicator electrodes like metallic electrodes, membrane electrodes, and gas sensing probes. Direct potentiometry and potentiometric titration techniques are briefly mentioned.
Potentiometry involves measuring the potential of electrochemical cells under conditions of no current flow. There are two types - direct potentiometry measures the potential of indicator electrodes related to analyte concentration, while indirect potentiometry involves measuring potential changes during titrations. A potentiometric cell consists of a reference electrode that maintains a constant potential, an indicator electrode whose potential varies with analyte concentration, and a salt bridge. The Nernst equation describes the relationship between electrode potential and analyte concentration or activity.
Polarographic analysis is a voltammetry technique that uses a dropping mercury electrode (DME) or static mercury drop electrode (SMDE) to measure the current resulting from the electrolysis of electroactive species at controlled potentials. It involves applying a potential between a mercury working electrode and a reference electrode, like a saturated calomel electrode, while measuring the current. The current-voltage curve, or polarogram, reveals information about the species present in solution, including qualitative and quantitative analysis through measurements of diffusion current and half-wave potential. Polarography takes advantage of mercury's wide cathodic potential range and its ability to renew its surface between drops.
This document discusses potentiometric analysis and its applications. Potentiometry involves measuring the potential difference between electrodes placed in a sample solution as the concentration of ions changes, such as during acid-base, redox, complexometric, and precipitation titrations. Some key applications of potentiometry include determining electrolyte levels in clinical samples, analyzing ions in environmental samples like water, and measuring properties in various industries like food processing, detergent manufacturing, and agriculture.
Polarography uses a dropping mercury electrode (DME) to measure the current flowing through an electrochemical cell as a function of the applied potential. A polarogram plots this current versus potential and provides qualitative and quantitative information about species undergoing oxidation or reduction reactions. Jaroslav Heyrovsky invented the polarographic method in 1922 and won the Nobel Prize for his contributions to electroanalytical chemistry. All modern voltammetric methods originate from polarography. The DME provides advantages like a reproducible surface area and the ability to form amalgams with metal ions.
This document discusses potentiometry, which is an electroanalytical technique that measures the potential (voltage) of electrochemical cells containing indicator and reference electrodes. It involves using electrodes to measure voltages generated from chemical reactions. Various types of electrodes are described including metal, ion-selective, glass membrane, liquid membrane, and crystalline membrane electrodes. Applications of potentiometry include ion concentration measurements, pH measurements, and potentiometric titrations.
This document discusses potentiometry, which involves measuring the potential or emf of a solution using an indicator electrode that responds to changes in potential or pH and a reference electrode with a stable, known potential. It describes common reference electrodes like the hydrogen, saturated calomel, and silver-silver chloride electrodes. It also discusses indicator electrodes like the glass and antimony electrodes and ion-selective electrodes. Potentiometric titrations can be used to determine endpoints by measuring potential changes during titration.
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.
Amperometry refers to the measurement of current under a constant applied voltage and under these conditions it is the concentration of analyte which determine the magnitude of current.
In Amperometric titrations, the potential applied between the indicator electrode (dropping mercury electrode) and the appropriate depolarizing reference electrode (saturated calomel electrode) is kept constant and current through the electrolytic cell is then measured on the addition of each increment of titrating solution. It is a form of quantitative analysis.
Otherwise called as Polarographic or polarometric titrations.
Polarography is an electroanalytical technique that measures the current between two electrodes in a solution. It can be used for both qualitative and quantitative analysis. The document discusses the principle, instrumentation, types of currents, and applications of polarography. Polarography involves applying a voltage to a dropping mercury electrode and reference electrode in an electrolyte solution and measuring the resulting current, which provides information about electroactive species in the solution.
Polarography is an electroanalytical technique that uses a dropping mercury electrode (DME) and measures the current between two electrodes when a gradually increasing voltage is applied. The current-voltage curve obtained is used to determine analyte concentration from the diffusion current and identify species from the characteristic half-wave potential. The Ilkovic equation relates diffusion current to analyte properties like concentration, number of electrons involved, and diffusion coefficient. Polarography finds applications in qualitative and quantitative analysis of metals, drugs, and organic compounds.
Potentiometry is an analytical technique that measures the potential of electrochemical cells without drawing current. It involves using a reference electrode with a known potential and an indicator electrode whose potential varies with analyte concentration. The cell potential is measured and related to concentration using the Nernst equation. Common reference electrodes include the standard hydrogen electrode and saturated calomel electrode. Glass membrane and ion-selective electrodes are often used as indicator electrodes to detect specific ions like hydrogen or fluoride ions. Potentiometry finds applications in clinical analysis, environmental monitoring, and titration experiments.
Potentiometry involves measuring the potential difference between two electrodes under equilibrium conditions. There are two main types of electrodes - reference electrodes that maintain a constant potential, and indicator or working electrodes whose potential varies with ion concentration. Common reference electrodes include the standard hydrogen electrode, saturated calomel electrode, and silver/silver chloride electrode. Indicator electrodes include glass membrane electrodes for measuring pH and ion-selective electrodes that respond selectively to specific ions. Potentiometry is used for pH measurements, ion-selective measurements, and potentiometric titrations.
This document provides an overview of electrochemistry and electrochemical cells. It defines electrochemistry as the study of the relationship between chemical transformations and electrical energy. It describes the two main types of electrochemical cells - electrolytic cells, which convert electrical to chemical energy, and galvanic/voltaic cells, which convert chemical to electrical energy. Key aspects of electrochemical cells covered include the electrodes, electrode charges, redox reactions, cell notation, salt bridges, cell potential, and reference electrodes. The document also discusses indicator electrodes, such as glass pH electrodes and potentiometric titration methods.
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.
Potentiometric titration uses a potentiometer to determine the concentration of an analyte in solution. A potentiometer consists of an indicator electrode and a reference electrode placed in the solution. The potential difference between the electrodes is measured as titrant is added. When the endpoint of the titration is reached, there is an abrupt change in the measured potential that can be used to calculate the concentration of analyte. Potentiometric titration is a common volumetric technique used in electroanalytical chemistry.
Potentiometry, Electrochemical cell, construction and working of indicator an...Vandana Devesh Sharma
Potentiometry - Electrochemical cell -Construction and working of reference (Standard hydrogen, silver chloride electrode and calomel electrode)
Indicator electrodes (metal electrodes and glass electrode)
Methods to determine end point of potentiometric titration
and applications
Potentiometry is the method to find the concentration of solute in
A given solution by measuring the potential between two Electrodes
(reference and Indicator electrode) . Potentiometric titration involves
the measurement of the potential of the indicator electrode and
reference electrode.
In potentiometric titration reference and indicator electrodes are
immersed in the solution of particular analyte (titrand) and
potential of indicator electrode is measured with relation to
reference electrode.
Titrant is added in analyte (Titrand) and change in potential is noted
down.
At the end point there is sharp change in potential on indicator
electrode.
Graph is plotted between the indicator electrode potential and
volume of titrant added.
This method is used for determination of sharp end point.
Types of Potentiometric Titration
1. Acid-base titration 2. Redox Titration 3.Complexometric titration 4. Precipitation Titration
This document discusses potentiometry, which is a method of analysis that determines concentration by measuring potential difference between two electrodes without current flow. It describes the principle, reference electrodes like standard hydrogen electrode and saturated calomel electrode, indicator electrodes like glass electrode, and how potentiometric titration can determine the endpoint using methods like the normal titration curve, first derivative curve, and second derivative curve. Potentiometry provides advantages over visual indicator methods by not requiring indicators and allowing the same instrument to be used for different titrations.
Potentiometry is the field of electro-analytical chemistry in which potential is measured without current flow.
It is a method of analysis in which we determine the concentration of solute in solution and the potential difference between two electrodes.
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.
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.
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.
There are several types of electrodes classified by their composition and function. Reference electrodes like the standard hydrogen electrode (SHE) and saturated calomel electrode (SCE) maintain a known and constant potential used for comparison. The SHE represents the standard reduction potential but is difficult to maintain at standard conditions. The SCE uses a mercury/mercury chloride mixture and is easier to construct and maintain compared to the SHE. Indicator electrodes like the glass electrode are used in titration analysis, with the glass electrode potential indicating pH. Electrodes can also be classified as anodes, which experience oxidation, or cathodes, which undergo reduction.
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.
potentiometry and ion selective electrodeAnimikh Ray
This document discusses potentiometry and ion selective electrodes. It provides information on:
- Potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. This allows the cell composition to remain unchanged.
- Ion selective electrodes are used to measure specific ion concentrations in solution based on the potential difference between an indicator electrode immersed in the solution and a reference electrode.
- Common applications of potentiometry and ion selective electrodes include measuring electrolyte levels like sodium, potassium, calcium, and pH in clinical samples and environmental samples. This provides useful quantitative analysis in various fields like healthcare, agriculture, and food processing.
pH and Potentiometry, Potentiometric titrations, Electrodes used in Potentiometry, Standard Hydrougen electrode, calamel electrode, silver silver chloride electrode, glass electrode
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 and ion selective electrodesAnimikh Ray
This document discusses potentiometry and ion selective electrodes. It provides information on:
- Potentiometry measures the potential of an electrochemical cell under static conditions without drawing current. This allows the cell composition to remain unchanged.
- Ion selective electrodes are used to measure specific ion concentrations in solution based on the potential difference between an indicator electrode immersed in the solution and a reference electrode.
- Common clinical applications of potentiometry and ion selective electrodes include measuring electrolyte levels like sodium, potassium, calcium and pH in samples like blood and urine to evaluate conditions like hypo- or hypernatremia.
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.
The document provides information about instrumental methods of analysis taught as part of the Engineering Chemistry course at Sinhgad Institute of Technology, Lonavala. It discusses topics like conductometry, pHmetry and different types of electrodes - reference electrodes like calomel electrode and indicator electrodes like glass electrode. The key details provided include the course contents, objectives, outcomes, introduction to various analytical techniques and applications of instrumental methods in industries, agriculture, environment etc. Important concepts around electrode potential, measurement of potential using reference electrodes and construction of calomel electrode with its cell representation are also summarized.
Potentiometry is a technique that measures the potential or electromotive force (emf) of a solution using an indicator electrode and a reference electrode. The potential difference between the two electrodes is dependent on factors like pH, gas concentration, or analyte ion activity in the solution. Common types of electrodes used include glass membrane pH electrodes, ion-selective electrodes with liquid or crystalline membranes, and gas-sensing electrodes. Potentiometric measurements can be carried out via direct measurement, standard addition, or titration to determine analyte concentration.
Communicating effectively and consistently with students can help them feel at ease during their learning experience and provide the instructor with a communication trail to track the course's progress. This workshop will take you through constructing an engaging course container to facilitate effective communication.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
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In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
Philippine Edukasyong Pantahanan at Pangkabuhayan (EPP) CurriculumMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 𝟏)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
- Understand the goals and objectives of the Edukasyong Pantahanan at Pangkabuhayan (EPP) curriculum, recognizing its importance in fostering practical life skills and values among students. Students will also be able to identify the key components and subjects covered, such as agriculture, home economics, industrial arts, and information and communication technology.
𝐄𝐱𝐩𝐥𝐚𝐢𝐧 𝐭𝐡𝐞 𝐍𝐚𝐭𝐮𝐫𝐞 𝐚𝐧𝐝 𝐒𝐜𝐨𝐩𝐞 𝐨𝐟 𝐚𝐧 𝐄𝐧𝐭𝐫𝐞𝐩𝐫𝐞𝐧𝐞𝐮𝐫:
-Define entrepreneurship, distinguishing it from general business activities by emphasizing its focus on innovation, risk-taking, and value creation. Students will describe the characteristics and traits of successful entrepreneurs, including their roles and responsibilities, and discuss the broader economic and social impacts of entrepreneurial activities on both local and global scales.
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
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Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
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Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
2. Potentiometry
• When a metal is immersed in a solution containing its
own ions, Say, zinc in zinc sulphate solution, a potential
difference is established between the metal and the
solution. The potential difference E for an electrode
reaction
• is given by the expression:
• where R is the gas constant, T is the absolute
temperature, F the Faraday constant, n the charge
number of the ions, aM+ the activity of the ions in the
solution, and E0 is a constant dependent upon the metal.
3. • It is simplified by introducing the known values of R and
F, and converting natural logarithms to base 10 by
multiplying by 2.3026; it then becomes:
• If T = 25 c
• For many purposes in quantitative analysis, it is
sufficiently accurate to replace aM+ by cM+n, the ion
concentration (in moles per litre):
• The latter is a form of the Nernst equation.
4. Electrochemical cell
• An electrochemical cell consists of two
conductors called electrodes, each of
which is immersed in an electrolyte solution.
5. Cathodes and Anodes
• The cathode in an electrochemical cell is the electrode
at which reduction occurs.
• The anode is the electrode at which an oxidation takes
place.
• Cathodic reaction
• Anodic reaction
7. • The reference electrode in this diagram is a half-cell
with an accurately known electrode potential, Eref,
that is independent of the concentration of the analyte or
any other ions in the solution under study. It can be a
standard hydrogen electrode but seldom is because a
standard hydrogen electrode is somewhat troublesome
to maintain and use. By convention, the reference
electrode is always treated as the left hand electrode in
potentiometric measurements.
• The indicator electrode, which is immersed in a
solution of the analyte, develops a potential, Eind, that
depends on the activity of the analyte. Most indicator
electrodes used in potentiometry are selective in their
responses.
8. Salt bridge
• The third component of a potentiometric cell is a salt
bridge that prevents the components of the analyte
solution from mixing with those of the reference
electrode
• a potential develops across the liquid junctions at each
end of the salt bridge. These two potentials tend to
cancel one another if the mobilities of the cation and the
anion in the bridge solution are approximately the same.
Potassium chloride is a nearly ideal electrolyte for the
salt bridge because the mobilities of the K+ ion and the
Cl- ion are nearly equal. The net potential across the salt
bridge, Ej, is thereby reduced to a few millivolts or less.
9. The potential of the cell
• The first term in this equation, Eind, contains the
information that we are looking for—the concentration of
the analyte.
• To make a potentiometric determination of an analyte
then, we must measure a cell potential, correct this
potential for the reference and junction potentials, and
compute the analyte concentration from the indicator
electrode potential. Strictly, the potential of a galvanic
cell is related to the activity of the analyte. Only through
proper calibration of the electrode system with solutions
of known concentration can we determine the
concentration of the analyte.
12. Calomel Reference Electrodes
• Calomel reference electrodes consist of mercury in
contact with a solution that is saturated with mercury(I)
chloride (calomel) and that also contains a known
concentration of potassium chloride.
• Calomel half-cells can be represented as follows:
• where x represents the molar concentration of potassium
chloride in the solution.
• The electrode potential for this half-cell is determined by
the reaction and depends on the chloride concentration.
Thus, the KCl concentration must be specified in
describing the electrode.
13. • H-shape body of the electrode is
made of glass of dimensions
shown in the diagram.
• The right arm of the electrode
contains a platinum electrical
contact, a small quantity of
mercury/mercury(I) chloride paste
in saturated potassium chloride,
and a few crystals of KCl.
• The tube is filled with saturated
KCl to act as a salt bridge through
a piece of porous
• Vycor (“thirsty glass”) sealed in
the end of the left arm.
14. Silver – Silver Chloride electrode
• The most widely marketed reference electrode system
consists of a silver electrode immersed in a solution of
potassium chloride that has been saturated with silver
chloride:
• The electrode potential is determined by the half-reaction
• Normally, this electrode is prepared with either a
saturated or a 3.5 M potassium chloride solution
15. • a piece of glass tubing that has
a narrow opening at the bottom
connected to a Vycor plug for
making contact with the analyte
solution.
• The tube contains a silver wire
coated with a layer of silver
chloride that is immersed in a
potassium chloride solution
saturated with silver chloride.
16. • Silver–silver chloride electrodes have the
advantage that they can be used at
temperatures greater than 60°C, while
calomel electrodes cannot.
• On the other hand, mercury(II) ions react
with fewer sample components than do
silver ions (which can react with proteins,
for example). Such reactions can lead to
plugging of the junction between the
electrode and the analyte solution.
17. Indicator Electrodes
• An ideal indicator electrode responds rapidly
and reproducibly to changes in the concentration
of an analyte ion (or group of analyte ions).
Although no indicator electrode is absolutely
specific in its response, a few are now available
that are remarkably selective.
• Indicator electrodes are of three types:
– metallic,
– membrane,
– And ion-sensitive field effect transistors.
18. Metallic indicator electrodes
• It is convenient to classify metallic
indicator electrodes as
– electrodes of the first kind,
– electrodes of the second kind,
– and inert redox electrodes.
19. Electrodes of the First Kind
• An electrode of the first kind is a pure
metal electrode that is in direct equilibrium
with its cation in the solution.
• A single reaction is involved.
• For example, the equilibrium between a
copper and its cation Cu+2 is
• for which potential is given by
20. We often express the electrode potential
of the indicator electrode in terms of the
p-function of the cation
Plot of
Eind > px
21. Electrode systems of the first kind are not widely used
for potentiometric determinations for several reasons
1. Metallic indicator electrodes are not very selective
2. Many metal electrodes, such as zinc and cadmium, can only be
used in neutral or basic solutions
3. Other metals are so easily oxidized that they can be used only
when analyte solutions are deaerated to remove oxygen.
4. Certain harder metals, such as iron, chromium, cobalt, and
nickel, do not provide reproducible potentials. For these
electrodes, plots of Eind versus px yield slopes that differ
significantly and irregularly from the Theoretical values.
For these reasons, the only electrode systems of the first Kind
that have been used in potentiometry are Ag/Ag+ and hg/hg +2 in
neutral solutions and Cu/Cu +2, Zn/Zn +2, Cd/Cd +2, Bi/Bi +3, Ti/Ti +2,
and Pb/Pb +2 in deaerated solutions.
22. Electrodes of the Second Kind
• Metals not only serve as indicator electrodes for their
own cations but also respond to the activities of anions
that form sparingly soluble precipitates or stable
complexes with such cations.
• The potential of a silver electrode, for example,
correlates reproducibly with the activity of chloride ion in
a solution saturated with silver chloride.
• In this situation, the electrode reaction can be written as
• And
23. Electrodes of the Third Kind
• Inert Metallic Electrodes for Redox Systems
• several relatively inert conductors respond to redox
systems. Such materials as platinum, gold,
palladium, and carbon can be used to monitor
redox systems.
• For example, the potential of a platinum electrode
immersed in a solution containing cerium(III) and
cerium(IV) is
24. Membrane Electrode
• Glass electrode
• The indicator electrode consists of a
thin pH-sensitive glass membrane
sealed onto one end of a heavy-
walled glass or plastic tube.
• A small volume of dilute hydrochloric
acid saturated with silver chloride is
contained in the tube.
• The inner solution in some
electrodes is a buffer containing
chloride ion.
25.
26. • Corning 015 glass, which has been widely used for
membranes, consists of approximately 22% Na2O, 6% CaO,
and 72% SiO2.
• Membranes made from this glass exhibit excellent specificity to
hydrogen ions up to a pH of about 9.
• At higher pH values, however, the glass becomes somewhat
responsive to sodium as well as to other singly charged cations.
• Other glass formulations are now in use in which sodium and
calcium ions are replaced to various degree by barium and
lithium ions. These membranes have superior selectivity and
lifetime.
27. • a silicate glass used for membranes consists of an
infinite three-dimensional network of groups in which
each silicon atom is bonded to four oxygen atoms
and each oxygen atom is shared by two silicon
atoms.
• Within the empty spaces
(interstices) inside this structure
are enough cations to balance
the negative charge of the silicate
groups.
• Singly charged cations, such as
sodium and lithium, can move
around in the lattice and are
responsible for electrical
conduction within the membrane.
28. • The two surfaces of a glass membrane must be hydrated
before it will function as a pH electrode.
• Nonhygroscopic glasses show no pH function.
• Even hygroscopic glasses lose their pH sensitivity after
dehydration by storage over a desiccant.
• The effect is reversible, however, and the response of a
glass electrode can be restored by soaking it in water.
• The hydration of a pH-sensitive glass membrane involves
an ion-exchange reaction between singly charged cations
in the interstices of the glass lattice and hydrogen ions
from the solution.
• The process involves +1 cations exclusively because +2
and +3 cations are too strongly held within the silicate
structure to exchange with ions in the solution. The ion-
exchange reaction can then be written as
29. Potentiometric titration
• Potentiometric titrations provide data that are more reliable
than data from titrations that use chemical indicators and
are particularly useful with colored or turbid solutions and
for detecting the presence of unsuspected species.
• Potentiometric titrations have been automated in a variety
of different ways, and commercial titrators are available
from a number of manufacturers.
• Manual potentiometric titrations, on the other hand, suffer
from the disadvantage of being more time consuming than
those involving indicators.
30. Detection of end point
Second derrivative
Normal
first derrivative
End Point
End Point
End Point
31. voltammetry
• The term voltammetry refers to a group of electro-
analytical methods in which we acquire information about
the analyte by measuring current in an electrochemical cell
as a function of applied potential.
• When current proportional to analyte concentration is
monitored at a fixed potential, the technique is called
amperometry.
32. • In voltammetry, the current that develops in an electro-
chemical cell is measured under conditions of complete
concentration polarization.
• A polarized electrode is one to which we have applied a
voltage in excess of that predicted by the Nernst equation to
cause oxidation or reduction to occur.
• In contrast, potentiometric measurements are made at
currents that approach zero and where polarization is
absent.
• Voltammetry differs from coulometry in that, with
coulometry, measures are taken to minimize or compensate
for the effects of concentration polarization.
• Furthermore, in voltammetry, there is minimal consumption
of analyte, while in coulometry essentially all of the analyte
is converted to another state.