MindMap Gallery Potentiometric method and double indicator electrode amperometric titration method
Including reference electrode, double salt bridge saturated calomel electrode, saturated calomel electrode SCE, silver-silver chloride electrode, indicator electrode, potentiometric titration, permanent stop titration, etc.
Edited at 2021-11-20 16:45:07One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
Project management is the process of applying specialized knowledge, skills, tools, and methods to project activities so that the project can achieve or exceed the set needs and expectations within the constraints of limited resources. This diagram provides a comprehensive overview of the 8 components of the project management process and can be used as a generic template for direct application.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
One Hundred Years of Solitude is the masterpiece of Gabriel Garcia Marquez. Reading this book begins with making sense of the characters' relationships, which are centered on the Buendía family and tells the story of the family's prosperity and decline, internal relationships and political struggles, self-mixing and rebirth over the course of a hundred years.
Project management is the process of applying specialized knowledge, skills, tools, and methods to project activities so that the project can achieve or exceed the set needs and expectations within the constraints of limited resources. This diagram provides a comprehensive overview of the 8 components of the project management process and can be used as a generic template for direct application.
Potentiometric method and double indicator electrode amperometric titration method
Basic principles of potentiometry
electrochemical cell
Primary battery
Convert chemical energy into electrical energy and reduce negative oxygen to positive
Cell
Convert electrical energy into chemical energy
liquid junction potential
cause
Due to the different ion diffusion rates, the potential difference
Solution
salt bridge
The role of salt bridge
Separate the positive and negative electrolyte solutions to prevent them from mixing with each other
Communicate the internal circuit and eliminate the liquid junction potential
Stable electrode potential
Does not react with the solutions that make up the battery
Electrodes in potentiometric cells
reference electrode
Good reversibility, stable electrode potential, and good reproducibility
Does not change with the composition of the liquid to be tested
Saturated calomel electrode SCE
Composed of metallic mercury, calomel and saturated KCL solution
The internal structure is complex, and the potential will drift with temperature changes.
Silver-green silver electrode
Simple structure, high temperature resistance, prone to CI ion penetration
Double salt bridge saturated calomel electrode
Indicating electrode
The electrode potential changes with the activity of the measured ion
metal-based electrode
Ion selective electrode
Composite electrode Indicator electrode and reference electrode are combined together during production Soak in 3mol/LKCL
direct potentiometry
Determination of hydrogen ion activity
SCE is commonly used as reference electrode The indicating electrode is a glass electrode
pH glass electrode
Composition Silica
Measurement principles and methods
Note: The temperature of the standard buffer solution and the sample solution are consistent The accuracy of pH measurement depends on the standard buffer solution activation Stir constantly when measuring
Other ion activity measurements
Double indicator electrode amperometric titration/permanent stop titration
Principle and device
There is a reversible redox couple in the liquid to be tested, and current flows through it. There is an irreversible electric pair and there is no current Determine the end point according to the change in current during the titration process
End point determination method
Reversible Electron Couple Titration Reversible Electron Couple
Irreversible Electric Couple Titration Reversible Electric Couple
Sodium thiosulfate titration of iodine
reversible couple titration irreversible couple
Iodine elemental titration of sodium thiosulfate
Applications
Using sodium nitrite as the standard solution, permanently stop the titration of aromatic primary amine compounds
potentiometric titration
Principle and device: determined based on the change in battery electromotive force during the titration process A type of analysis method for titration end point, indicator electrode
Final method point determined
E-V curve method: corresponding to the turning point of the curve The abscissa value is the titration end point
△E/△V-V curve method: The volume corresponding to the highest point of the curve is the volume of the end point
Interpolation
Electrochemical classification
potentiometric method
Voltammetry
conductivity method
electrolysis
High accuracy, good reproducibility, good stability; not interfered by solution color, high sensitivity, Good selectivity, simple instrument setup, and wide application