This document discusses methods for determining transport numbers during electrolysis. It describes Hittorf's method and the moving boundary method. Hittorf's method involves electrolysis in a two-limbed vessel and analyzing changes in electrolyte concentration. The fraction of total current carried by each ion is equal to its transport number. The moving boundary method directly observes ion migration using a conductivity cell containing two solutions that form a boundary. Application of a current causes the boundary to move as ions migrate.
Crystal field theory proposes that ligands behave as point charges that create an electric field around a central metal ion. This affects the energies of the metal's d-orbitals. In an octahedral complex, ligands along the x, y, and z axes interact more strongly with the dz2 and dx2-y2 orbitals, splitting them into the higher-energy eg set. The dxy, dyz, and dxz orbitals interact less with ligands between the axes, forming the lower-energy t2g set. This splitting of orbital energies, described by the crystal field splitting parameter Δ0, helps explain differences in complexes' magnetic properties.
Basic Terminology,Heat, energy and work, Internal Energy (E or U),First Law of Thermodynamics, Enthalpy,Molar heat capacity, Heat capacity,Specific heat capacity,Enthalpies of Reactions,Hess’s Law of constant heat summation,Born–Haber Cycle,Lattice energy,Second law of thermodynamics, Gibbs free energy(ΔG),Bond Energies,Efficiency of a heat engine
1. Electrochemistry deals with the transformation of electrical energy to chemical energy and vice versa. It involves the chemical applications of electricity.
2. An electrolytic cell converts electrical energy to chemical energy, while an electrochemical cell converts chemical energy to electrical energy.
3. Arrhenius' theory of electrolytic dissociation states that when an electrolyte dissolves in water, it breaks up into ions. There is a dynamic equilibrium between the ionized and non-ionized molecules. The degree of ionization depends on factors like the ionization constant.
Mesomeric effect is the permanent shifting of π-electrons from multiple bonds to single bonds or lone pairs, which mainly operates in conjugated double bond systems. There are two types of mesomeric effects: -m effect from electron withdrawing groups containing double or triple bonds between heteroatoms, and +m effect from electron donating groups where the first atom has a negative charge or lone pair. The effects influence the electron density on benzene rings, with -m decreasing and +m increasing density at the ortho and para positions.
This document classifies and describes various types of hydrocarbons including alkanes, alkenes, alkynes, and benzene. It discusses their structures, methods of preparation from other compounds, and common chemical reactions. Key details provided include the IUPAC nomenclature rules for alkanes and cycloalkanes, reactions of alkenes with halogens, acids, and hydrogen, and benzene reactions such as nitration, sulfonation, halogenation, and Friedel-Crafts additions and acylations.
This document discusses methods for determining transport numbers during electrolysis. It describes Hittorf's method and the moving boundary method. Hittorf's method involves electrolysis in a two-limbed vessel and analyzing changes in electrolyte concentration. The fraction of total current carried by each ion is equal to its transport number. The moving boundary method directly observes ion migration using a conductivity cell containing two solutions that form a boundary. Application of a current causes the boundary to move as ions migrate.
Crystal field theory proposes that ligands behave as point charges that create an electric field around a central metal ion. This affects the energies of the metal's d-orbitals. In an octahedral complex, ligands along the x, y, and z axes interact more strongly with the dz2 and dx2-y2 orbitals, splitting them into the higher-energy eg set. The dxy, dyz, and dxz orbitals interact less with ligands between the axes, forming the lower-energy t2g set. This splitting of orbital energies, described by the crystal field splitting parameter Δ0, helps explain differences in complexes' magnetic properties.
Basic Terminology,Heat, energy and work, Internal Energy (E or U),First Law of Thermodynamics, Enthalpy,Molar heat capacity, Heat capacity,Specific heat capacity,Enthalpies of Reactions,Hess’s Law of constant heat summation,Born–Haber Cycle,Lattice energy,Second law of thermodynamics, Gibbs free energy(ΔG),Bond Energies,Efficiency of a heat engine
1. Electrochemistry deals with the transformation of electrical energy to chemical energy and vice versa. It involves the chemical applications of electricity.
2. An electrolytic cell converts electrical energy to chemical energy, while an electrochemical cell converts chemical energy to electrical energy.
3. Arrhenius' theory of electrolytic dissociation states that when an electrolyte dissolves in water, it breaks up into ions. There is a dynamic equilibrium between the ionized and non-ionized molecules. The degree of ionization depends on factors like the ionization constant.
Mesomeric effect is the permanent shifting of π-electrons from multiple bonds to single bonds or lone pairs, which mainly operates in conjugated double bond systems. There are two types of mesomeric effects: -m effect from electron withdrawing groups containing double or triple bonds between heteroatoms, and +m effect from electron donating groups where the first atom has a negative charge or lone pair. The effects influence the electron density on benzene rings, with -m decreasing and +m increasing density at the ortho and para positions.
This document classifies and describes various types of hydrocarbons including alkanes, alkenes, alkynes, and benzene. It discusses their structures, methods of preparation from other compounds, and common chemical reactions. Key details provided include the IUPAC nomenclature rules for alkanes and cycloalkanes, reactions of alkenes with halogens, acids, and hydrogen, and benzene reactions such as nitration, sulfonation, halogenation, and Friedel-Crafts additions and acylations.
This presentation consists of three topics that are:
1. conductance of electrolytic solution
2. Specific Conductance, Molar Conductance & Equivalent Conductance
3. Kohlrausch's Law
Hot Atom Chemistry: Szilard Chalmers ProcessRosmy Davis
The Szilard-Chalmers effect describes the separation of radioactive isotopes from a nuclear reaction using chemical processes. When a neutron is captured by an atom, the resulting nuclear recoil can break the chemical bond between that atom and the molecule it is bound to. This allows separation of the radioactive atom from the original molecule using standard chemical techniques. The effect has applications in producing radioactive tracers and determining nuclear properties like internal conversion coefficients.
1. Polymers are large macromolecules formed by chemical bonding of repeating structural units called monomers.
2. Polymers can be classified based on their source, structure, intermolecular forces, process of polymerization, types of monomers, and biodegradability.
3. Common natural polymers include rubber from plants and silk/wool from animals, while synthetic polymers are man-made like nylon, polyester, and neoprene. Semisynthetic polymers are derived from natural polymers like rayon.
Electrochemistry involves the movement of electrons during redox reactions. Redox reactions involve the oxidation of one species and the reduction of another. Voltaic cells generate electric current through redox reactions. They consist of two half-cells where oxidation and reduction occur, separated by a salt bridge or porous disk. Batteries like car batteries and dry cells are examples of voltaic cells. The Nernst equation relates the standard potential of a cell to its potential under non-standard conditions based on concentrations of reactants and products.
1) Molecular term symbols employ symmetry labels from group theory to mark the electronic energy levels of diatomic molecules similarly to atomic term symbols under the Russell-Saunders coupling scheme.
2) Heteronuclear diatomic molecules have C∞v symmetries and homonuclear ones have D∞h symmetries, with their irreducible representations symbolized using notations like Σ, Π, Δ. Term symbols include quantum numbers like Λ (orbital angular momentum), Ω (total angular momentum), and S (spin multiplicity).
3) Selection rules for electronic transitions between terms include ΔΛ = 0, ±1; ΔS = 0; and ΔΩ = 0, ±
This document discusses haloalkanes and haloarenes. It begins by classifying haloalkanes based on the number of halogen atoms attached to the carbon. It then discusses IUPAC and common naming of these compounds. It describes the nature of C-X bonds and how bond length, enthalpy, stability, and reactivity vary based on the halogen atom. Methods of preparing haloalkanes from alcohols and hydrocarbons are presented. The document discusses physical properties, nucleophilic substitution reactions, elimination reactions, and reactions of haloarenes such as with Grignard reagents and the Wurtz reaction. Health effects of some common haloalkanes like dichloromethane and trich
This document summarizes Crystal Field Theory, which considers the electrostatic interactions between metal ions and ligands. It describes ligands and metal ions as point charges that can have attractive or repulsive forces. This causes the d orbitals of the metal ion to split into two sets depending on if the field created by the ligands is weak or strong. The theory explains color in coordination compounds as being caused by d-d electron transitions under the influence of ligands. However, it has limitations like not accounting for other metal orbitals or the partial covalent nature of metal-ligand bonds.
1. Photochemistry is the study of chemical reactions caused by the absorption of light. It involves photochemical reactions, which require light for initiation, as well as photophysical processes during the de-excitation of excited molecules.
2. Key concepts in photochemistry include Grotthuss-Draper law, Lambert's law, Beer's law, and Stark-Einstein law of photochemical equivalence. Quantum yield determines the efficiency of photochemical reactions.
3. Photochemistry examines differences between photochemical and thermal reactions. It also explores photochemical processes like fluorescence, phosphorescence, internal conversion, and intersystem crossing depicted in Jablonski diagrams.
The document discusses the modern periodic law and periodic trends in atomic properties. It can be summarized as follows:
1. The modern periodic law states that the properties of elements are periodic functions of their atomic numbers. Elements are arranged in the periodic table based on increasing atomic number and similar outer electron configurations that repeat at regular intervals.
2. The periodic table is divided into blocks based on orbital types. Elements show trends in properties within periods and down groups, including decreasing atomic radius and increasing ionization energy with increasing atomic number. Electron affinity also tends to decrease down groups.
3. Successive ionization energies increase as more energy is required to remove additional electrons. Stability of half-filled and fully-filled
This presentaion describes about the basic principle effects in organic chemistry like inductive,mesomeric,electromeric, resonance and hyperconjugation. this presentation contains some JAM competitive questions.
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.
The pptx on complexometric titrations, EDTA titration, Why EDTA is used in complexometric titration, Classification of EDTA titration, EDTA titration curve etc.
B.tech. ii engineering chemistry unit 4 B organic chemistryRai University
Organic reactions and their mechanisms are described. Key topics covered include nucleophiles and electrophiles, reaction types (addition, elimination, substitution), and organic intermediates. Electron displacement effects such as inductive, mesomeric, electromeric and inductometric effects are also discussed. Common organic reactions like nitration, halogenation and nucleophilic aromatic substitution are summarized.
This document discusses electronic displacement in organic compounds. It describes two types of electronic displacement: permanent displacement including inductive, resonance, and mesomeric effects; and temporary displacement through electromeric effects. Inductive effects are further broken down into +I effects where groups donate electron density and -I effects where groups withdraw electron density. Examples of inductive effects include their impact on acid/base strength, stability of carbocations/carbanions, and dipole moments.
This document discusses several types of metalloproteins and their functions. It begins by defining metalloproteins as proteins bound by at least one metal ion, with the metal ions usually coordinated by nitrogen, sulfur, or oxygen atoms in the protein. Several examples of metalloproteins are provided, including their metal components and functions. For example, ferritin stores iron, carbonic anhydrase catalyzes the interconversion of carbon dioxide and water, and hemocyanin and hemerythrin are dioxygen carriers in mollusks/arthropods and marine invertebrates respectively. The roles of metalloproteins in processes like the electron transport chain and nitrogen fixation in plants are also summarized.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
This document provides an overview of molecular spectroscopy techniques, including rotational spectroscopy, vibrational spectroscopy, and absorption and emission spectroscopy. Rotational spectroscopy uses microwave spectroscopy to study the quantized rotational energy levels of molecules. Vibrational spectroscopy uses infrared spectroscopy to analyze the quantized vibrational energy levels of bonds as they stretch, bend, and vibrate. Absorption and emission spectroscopy examines how molecules absorb and emit photons during electronic transitions between energy levels.
This document discusses electrochemistry and provides details about electrochemical cells. It contains the following key points:
1. Electrochemistry is the study of production of electricity from chemical reactions and use of electrical energy to drive non-spontaneous reactions.
2. An electrochemical cell converts chemical energy to electrical energy (galvanic/voltaic cell) or electrical energy to chemical energy (electrolytic cell).
3. A Daniell cell is a voltaic cell that generates a voltage of 1.1V from the redox reaction of zinc and copper. Measurement of electrode potentials and the Nernst equation are also discussed.
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bond
This presentation consists of three topics that are:
1. conductance of electrolytic solution
2. Specific Conductance, Molar Conductance & Equivalent Conductance
3. Kohlrausch's Law
Hot Atom Chemistry: Szilard Chalmers ProcessRosmy Davis
The Szilard-Chalmers effect describes the separation of radioactive isotopes from a nuclear reaction using chemical processes. When a neutron is captured by an atom, the resulting nuclear recoil can break the chemical bond between that atom and the molecule it is bound to. This allows separation of the radioactive atom from the original molecule using standard chemical techniques. The effect has applications in producing radioactive tracers and determining nuclear properties like internal conversion coefficients.
1. Polymers are large macromolecules formed by chemical bonding of repeating structural units called monomers.
2. Polymers can be classified based on their source, structure, intermolecular forces, process of polymerization, types of monomers, and biodegradability.
3. Common natural polymers include rubber from plants and silk/wool from animals, while synthetic polymers are man-made like nylon, polyester, and neoprene. Semisynthetic polymers are derived from natural polymers like rayon.
Electrochemistry involves the movement of electrons during redox reactions. Redox reactions involve the oxidation of one species and the reduction of another. Voltaic cells generate electric current through redox reactions. They consist of two half-cells where oxidation and reduction occur, separated by a salt bridge or porous disk. Batteries like car batteries and dry cells are examples of voltaic cells. The Nernst equation relates the standard potential of a cell to its potential under non-standard conditions based on concentrations of reactants and products.
1) Molecular term symbols employ symmetry labels from group theory to mark the electronic energy levels of diatomic molecules similarly to atomic term symbols under the Russell-Saunders coupling scheme.
2) Heteronuclear diatomic molecules have C∞v symmetries and homonuclear ones have D∞h symmetries, with their irreducible representations symbolized using notations like Σ, Π, Δ. Term symbols include quantum numbers like Λ (orbital angular momentum), Ω (total angular momentum), and S (spin multiplicity).
3) Selection rules for electronic transitions between terms include ΔΛ = 0, ±1; ΔS = 0; and ΔΩ = 0, ±
This document discusses haloalkanes and haloarenes. It begins by classifying haloalkanes based on the number of halogen atoms attached to the carbon. It then discusses IUPAC and common naming of these compounds. It describes the nature of C-X bonds and how bond length, enthalpy, stability, and reactivity vary based on the halogen atom. Methods of preparing haloalkanes from alcohols and hydrocarbons are presented. The document discusses physical properties, nucleophilic substitution reactions, elimination reactions, and reactions of haloarenes such as with Grignard reagents and the Wurtz reaction. Health effects of some common haloalkanes like dichloromethane and trich
This document summarizes Crystal Field Theory, which considers the electrostatic interactions between metal ions and ligands. It describes ligands and metal ions as point charges that can have attractive or repulsive forces. This causes the d orbitals of the metal ion to split into two sets depending on if the field created by the ligands is weak or strong. The theory explains color in coordination compounds as being caused by d-d electron transitions under the influence of ligands. However, it has limitations like not accounting for other metal orbitals or the partial covalent nature of metal-ligand bonds.
1. Photochemistry is the study of chemical reactions caused by the absorption of light. It involves photochemical reactions, which require light for initiation, as well as photophysical processes during the de-excitation of excited molecules.
2. Key concepts in photochemistry include Grotthuss-Draper law, Lambert's law, Beer's law, and Stark-Einstein law of photochemical equivalence. Quantum yield determines the efficiency of photochemical reactions.
3. Photochemistry examines differences between photochemical and thermal reactions. It also explores photochemical processes like fluorescence, phosphorescence, internal conversion, and intersystem crossing depicted in Jablonski diagrams.
The document discusses the modern periodic law and periodic trends in atomic properties. It can be summarized as follows:
1. The modern periodic law states that the properties of elements are periodic functions of their atomic numbers. Elements are arranged in the periodic table based on increasing atomic number and similar outer electron configurations that repeat at regular intervals.
2. The periodic table is divided into blocks based on orbital types. Elements show trends in properties within periods and down groups, including decreasing atomic radius and increasing ionization energy with increasing atomic number. Electron affinity also tends to decrease down groups.
3. Successive ionization energies increase as more energy is required to remove additional electrons. Stability of half-filled and fully-filled
This presentaion describes about the basic principle effects in organic chemistry like inductive,mesomeric,electromeric, resonance and hyperconjugation. this presentation contains some JAM competitive questions.
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.
The pptx on complexometric titrations, EDTA titration, Why EDTA is used in complexometric titration, Classification of EDTA titration, EDTA titration curve etc.
B.tech. ii engineering chemistry unit 4 B organic chemistryRai University
Organic reactions and their mechanisms are described. Key topics covered include nucleophiles and electrophiles, reaction types (addition, elimination, substitution), and organic intermediates. Electron displacement effects such as inductive, mesomeric, electromeric and inductometric effects are also discussed. Common organic reactions like nitration, halogenation and nucleophilic aromatic substitution are summarized.
This document discusses electronic displacement in organic compounds. It describes two types of electronic displacement: permanent displacement including inductive, resonance, and mesomeric effects; and temporary displacement through electromeric effects. Inductive effects are further broken down into +I effects where groups donate electron density and -I effects where groups withdraw electron density. Examples of inductive effects include their impact on acid/base strength, stability of carbocations/carbanions, and dipole moments.
This document discusses several types of metalloproteins and their functions. It begins by defining metalloproteins as proteins bound by at least one metal ion, with the metal ions usually coordinated by nitrogen, sulfur, or oxygen atoms in the protein. Several examples of metalloproteins are provided, including their metal components and functions. For example, ferritin stores iron, carbonic anhydrase catalyzes the interconversion of carbon dioxide and water, and hemocyanin and hemerythrin are dioxygen carriers in mollusks/arthropods and marine invertebrates respectively. The roles of metalloproteins in processes like the electron transport chain and nitrogen fixation in plants are also summarized.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
This document provides an overview of molecular spectroscopy techniques, including rotational spectroscopy, vibrational spectroscopy, and absorption and emission spectroscopy. Rotational spectroscopy uses microwave spectroscopy to study the quantized rotational energy levels of molecules. Vibrational spectroscopy uses infrared spectroscopy to analyze the quantized vibrational energy levels of bonds as they stretch, bend, and vibrate. Absorption and emission spectroscopy examines how molecules absorb and emit photons during electronic transitions between energy levels.
This document discusses electrochemistry and provides details about electrochemical cells. It contains the following key points:
1. Electrochemistry is the study of production of electricity from chemical reactions and use of electrical energy to drive non-spontaneous reactions.
2. An electrochemical cell converts chemical energy to electrical energy (galvanic/voltaic cell) or electrical energy to chemical energy (electrolytic cell).
3. A Daniell cell is a voltaic cell that generates a voltage of 1.1V from the redox reaction of zinc and copper. Measurement of electrode potentials and the Nernst equation are also discussed.
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bond
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 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.
1. The document discusses electrode potential and how it is measured. Electrode potential is the tendency of an electrode to gain or lose electrons when in contact with its own ions in solution.
2. Oxidation occurs at the anode where electrons are lost, and reduction occurs at the cathode where electrons are gained. The standard hydrogen electrode is used as a reference to measure other electrode potentials.
3. Electrode potentials can be oxidation potentials if the electrode loses electrons or reduction potentials if it gains electrons. Nernst theory explains how solution pressure and osmotic pressure determine electrode behavior.
The document discusses corrosion, including its types, why we prevent it, and various electrochemical principles related to corrosion. It defines corrosion as the destruction of metals by chemical and electrochemical attack from the environment. There are two main types of corrosion: chemical (dry) corrosion which occurs without moisture, and electrochemical (wet) corrosion, which is the most common and occurs in the presence of moisture via an electrochemical cell. The document outlines several electrochemical concepts like the Pilling Bedworth rule, electrochemical series, Nernst equation, standard electrodes, and Pourbaix and Ellingham diagrams which can be used to understand and predict corrosion reactions and products.
The document discusses corrosion, including its types, why we prevent it, and several related concepts from electrochemistry. It defines corrosion as the destruction of metals by chemical and electrochemical attack from the environment. There are two main types: chemical corrosion from oxygen and electrochemical corrosion, which occurs in the presence of moisture and produces an electrochemical cell. The document outlines several concepts to understand and control corrosion, including the Pilling-Bedworth rule, electrochemical series, Nernst equation, standard electrodes, and Pourbaix and Ellingham diagrams.
The document discusses corrosion, including its types, why we prevent it, and several related concepts from electrochemistry. It defines corrosion as the destruction of metals by chemical and electrochemical attack from the environment. There are two main types: chemical corrosion from oxygen and electrochemical corrosion, which occurs in the presence of moisture and produces an electrochemical cell. The document outlines several electrochemical concepts like the Pilling Bedworth rule, electrochemical series, Nernst equation, standard electrodes, and Pourbaix and Ellingham diagrams, which can be used to understand and predict corrosion reactions.
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 summarizes different types of chemical bonds including ionic bonds, covalent bonds, and polar covalent bonds. It discusses bond energy, electronegativity, dipole moments, and Lewis structures. Key concepts covered include how ionic bonds form between a metal and nonmetal, how covalent bonds share electron pairs, and how polar covalent bonds have unequal electron sharing.
This document discusses different types of chemical bonds including ionic bonds, covalent bonds, and polar covalent bonds. It explains how ionic bonds form between a metal and nonmetal when electrons are transferred, covalent bonds form through shared electron pairs, and polar covalent bonds result from unequal electron sharing. The document also covers bond energies, dipole moments, electronegativity, and Lewis structures.
This document discusses a lecture on electrochemistry. It covers key concepts like electrolysis, Faraday's laws of electrolysis, and electrochemical cells.
Some key points covered include that electrolysis is the decomposition of a compound by an electric current, and involves oxidation and reduction reactions. Faraday's first law states the mass of a substance produced by electrolysis is directly proportional to the quantity of electricity used. Faraday's second law relates the masses of different substances deposited to their equivalent masses. An electrochemical cell uses a redox reaction to produce an electrical current.
1. Electrochemistry involves electron transfer between chemical species in oxidation-reduction reactions.
2. Oxidation and reduction half-reactions can be balanced using the half-reaction method and combined to give the overall redox reaction.
3. Voltaic cells harness the energy of spontaneous redox reactions by allowing electrons to flow through an external circuit, and cell potential depends on the relative reduction potentials of the half-reactions.
Class XII Electrochemistry - Nernst equation.Arunesh Gupta
This document provides an overview of electrochemistry and some key concepts. It begins by defining electrochemistry as the study of how spontaneous chemical reactions can produce electricity and how electrical energy can drive non-spontaneous reactions. It then discusses several applications of electrochemistry including metal production, electroplating, and batteries. The document goes on to define conductors and the differences between metallic and electrolytic conduction. It also introduces concepts like galvanic cells, salt bridges, standard electrode potentials, and the electrochemical series. In summary, the document provides a broad introduction to fundamental electrochemistry topics and concepts.
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.
Revision notes on redox reactions and electrochemistryAayashaNegi
Electrochemistry deals with chemical changes caused by electric current. Substances can be conductors or non-conductors of electricity. Conductors include metals and electrolytes, which conduct by electron or ion movement respectively. Redox reactions involve the transfer of electrons from one species to another, changing their oxidation states. Balancing redox reactions uses half-reactions and ensures equal electron transfer.
Revision notes on redox reactions and electrochemistryAayashaNegi
Electrochemistry deals with chemical changes caused by electric current and the conversion between chemical and electrical energy. Substances can be conductors or non-conductors of electricity. Conductors include metals and electrolyte solutions, which conduct electricity through electron or ion movement respectively. Key differences between metallic and electrolytic conduction include whether chemical changes occur and if matter is transferred during the process.
Corrosion is a natural process that deteriorates materials, commonly metals, due to chemical or electrochemical reactions with their environment. It's a significant concern across various industries, including infrastructure, manufacturing, and transportation. The effects of corrosion can range from minor aesthetic damage to catastrophic structural failure, leading to enormous economic costs and safety hazards.
Several factors influence corrosion, including environmental conditions such as moisture, temperature, pH levels, and the presence of corrosive agents like oxygen, sulfur compounds, and salts. Additionally, the material's composition and microstructure play crucial roles in its susceptibility to corrosion.
To mitigate corrosion and prolong the lifespan of materials, various protection methods are employed:
Barrier Protection: This involves applying coatings or barriers to physically isolate the material from its environment. Common barrier materials include paints, polymer coatings, and enamels. These coatings create a protective layer that prevents corrosive agents from reaching the underlying material.
Cathodic Protection: This method involves making the metal to be protected the cathode of an electrochemical cell, thus reducing its corrosion rate. Cathodic protection can be achieved through sacrificial anodes, where a more reactive metal (such as zinc or magnesium) is connected to the metal to be protected, sacrificing itself to protect the base metal.
Anodic Protection: Conversely, anodic protection works by polarizing the metal to be protected to make it the anode in an electrochemical cell. This method is suitable for metals that exhibit passivity, such as stainless steel. By maintaining the metal in its passive state, its corrosion rate is significantly reduced.
Inhibitors: Corrosion inhibitors are chemicals that are added to the environment surrounding the metal to reduce its corrosion rate. Inhibitors work by adsorbing onto the metal surface, forming a protective layer that blocks corrosive agents from reaching the metal. Common inhibitors include organic compounds, chromates, and phosphates.
Alloying: Alloying involves mixing the base metal with other elements to improve its corrosion resistance. For example, stainless steel contains chromium, which forms a passive oxide layer on the surface, protecting the underlying metal from corrosion.
Design Modification: Sometimes, corrosion can be mitigated through design modifications that minimize exposure to corrosive environments or improve drainage to prevent the accumulation of moisture.
Each protection method has its advantages and limitations, and the choice of method depends on factors such as the material, the environment, cost considerations, and the required durability. In many cases, a combination of protection methods may be employed to provide optimal corrosion resistance.
Overall, effective corrosion protection is essential for maintaining the integrity and longevity of
Rd Madan bioinorganic chemistry pdf chaptersminanbmb41
This document discusses standard electrode potentials and how they are measured. It provides details on:
1) How a double electric layer forms at the interface of a metal and its ionic solution, creating a potential difference called the electrode potential.
2) The standard hydrogen electrode, which is assigned a potential of zero volts and used as a reference to measure other electrode potentials.
3) How the potential of a metal-ion electrode is determined by constructing a cell with it and the standard hydrogen electrode and measuring the cell voltage.
4) Factors that influence electrode potential values, such as metal identity, ion concentration, and temperature.
5) A table of standard reduction potentials for some common half
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...Sérgio Sacani
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
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with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
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0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
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PPT on Sustainable Land Management presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...PsychoTech Services
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
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Signatures of wave erosion in Titan’s coastsSérgio Sacani
The shorelines of Titan’s hydrocarbon seas trace flooded erosional landforms such as river valleys; however, it isunclear whether coastal erosion has subsequently altered these shorelines. Spacecraft observations and theo-retical models suggest that wind may cause waves to form on Titan’s seas, potentially driving coastal erosion,but the observational evidence of waves is indirect, and the processes affecting shoreline evolution on Titanremain unknown. No widely accepted framework exists for using shoreline morphology to quantitatively dis-cern coastal erosion mechanisms, even on Earth, where the dominant mechanisms are known. We combinelandscape evolution models with measurements of shoreline shape on Earth to characterize how differentcoastal erosion mechanisms affect shoreline morphology. Applying this framework to Titan, we find that theshorelines of Titan’s seas are most consistent with flooded landscapes that subsequently have been eroded bywaves, rather than a uniform erosional process or no coastal erosion, particularly if wave growth saturates atfetch lengths of tens of kilometers.
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Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
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PPT on Direct Seeded Rice presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
1. The lattice enthalpy cannot be measured directly and so we make use
of other known enthalpies and link them together with an enthalpy
cycle.
This enthalpy cycle is the Born-Haber cycle. This cycle devised by
Born and Haber in 1919 relates the lattice energy of a crystal to other
thermochemical data.
What do we mean by lattice enthalpy?
For an ionic compound the lattice enthalpy is the enthalpy change
when one mole of solid in its standard state is formed from its ions in
the gaseous state.
The enthalpies of sublimation and dissociation and the ionization
energy are positive since energy is supplied to the system. The
electron affinity and lattice energy ate negative since energy is
evolved in these processes.
2.
3. According to Hess's law, the overall energy change in a process depends only on
the energy of the initial and final states and not on the route taken. Thus the
enthalpy of formation of ΔHf is the algebraic sum of the terms going round the
cycle.
∆𝐻𝑓 = ∆𝐻𝑠 + 𝐼 +
1
2
∆𝐻𝑑 + 𝐸 + 𝑈
E = -348.6 kJmol-1
381.2 = +108.4 + 495.4 + 120.9 + 𝐸 − 757.3
For NaCl,
It is useful to know the lattice energy, as a guide to the solubility of the crystal.
When a solid dissolves, the crystal lattice must be broken up (which requires that
energy is put in). The ions so formed are solvated (with the evolution of energy).
When the lattice energy is high a large amount of energy is required to break the
lattice. It is unlikely that the enthalpy of solvation will be big enough (and evolve
sufficient energy to offset this), so the substance will probably be insoluble.
4. When a metal is immersed in water, or a solution containing its -own ions, the metal
tends to lose positive metal ions into the solution. Thus the metal acquires a negative
charge.
Standard Electrode Potential and Electrochemical Series
𝑀𝑛+
ℎ𝑦𝑑𝑟𝑎𝑡𝑒𝑑 + 𝑛𝑒 ↔ 𝑀(𝑠𝑜𝑙𝑖𝑑)
The tendency of an electrode to gain or loose electron when it is in contact with its
own solution is called „electrode potential‟. Tendency to gain electron is called
Reduction potential while tendency to loose electron is called Oxidation Potential.
It is not possible to determine experimentally the potential of a single electrode, it is
only the difference of potential between two electrodes that we can measure. The
standard hydrogen electrode is used for this purpose whose potential is arbitrarily
fixed to zero.
Standard Hydrogen Electrode:
Platinized platinum electrode which is saturate with hydrogen at one atmosphere
pressure and immersed in a solution of H3O+ ions at unit activity (1M concentration).
5. • If the elements are arranged in order of increasing standard electrode potentials. the
resulting Table is called the electrochemical series.
Electrochemical Series:
• In the electrochemical series the most electropositive elements are at the top and the least
electropositive. at the bottom.
• The greater the negative value of the potential. the greater isthe tendency for a metal to
ionize. Thus a metal high in the electrochemical series will displace another metal lower
down the series from solution.
• For example, iron is above copper in the. electrochemical series. and scrap iron is
sacrificed.to displace Cu2+ ions from solution of CuSO4 in the recovery of metallic copper.
Fe + Cu2+ Fe2+ + Cu
Redox couple Ox/Red Cu2+/Cu
6. • The potential suggests if the reaction is possible or not but does not suggest the kinetics of
the reaction (rate of reaction).
• The spontaneous nature of reaction can easily be predicted.
∆𝐺 = −𝑛𝐹𝐸°
ΔG = changes in Gibb‟s free energy
n = valency of the ions
F = Faraday constant
E⁰ = standard electrode potential
ΔG = negative- spontaneous
ΔG = positive- nonspontaneous
Energy Cycle for Electrode Potential:
Electrolysis: “The substances whose aqueous solution undergo decomposition into ions when
electric current is passed through them are known as electrolytes and the whole process is
known as electrolysis or electrolytic decomposition.”
Here there is conversion of electrical energy into chemical energy i.e., electrical energy is
supplied to the electrolytic solution to bring about the redox reaction (i.e., electrolysis) which
is non- spontaneous and takes place only when electrical energy is supplied.
7.
8. However, hydrogen and other gases often require a considerably higher voltage than the
theoretical potential before they discharge. For hydrogen, this extra or over-voltage may be
0.8 volts, and thus it is possible to electrolyse zinc salts in aqueous solution.
When a solution is electrolysed the externally applied potential must overcome the
electrode potential. The minimum voltage necessary to cause deposition is equal and
opposite in sign to the potential between the solution and the electrode.
Elements low down in the series discharge first; thus Cu2+ discharges before H+, so copper
may be electrolysed in aqueous solution.
Several factors affect the value of the standard potential. The conversion of M to M+ in
aqueous solution may be considered in a series of steps:
1. sublimation of a solid metal
2. Ionization of a gaseous metal atom
3. Hydration of a gaseous ion
These are best considered in a Born-Haber type of cycle
9. The enthalpy of sublimation and the ionization energy are positive since energy must be put
into the . system, and the enthalpy of hydration is negative since energy is evolved. Thus
𝑬 = +∆𝑯𝒔 + 𝑰 + ∆𝑯𝒉
10. Why Group I and II metals are more reactive as compared to transition metal ions?
Consider first a transition metal; Most transition metals have high melting points: hence the
enthalpy of sublimation is high. Similarly they are fairly small atoms and have high ionization
energies. Thus the value for the electrode potential E is low; and the metal has little tendency
to form ions: hence it is unreactive or noble.
In contrast the s-block metals (Groups I and II) have low melting points (hence low
enthalpies of sublimation), and the atoms are large and therefore have low ionization
energies. Thus the electrode potential E is high and the metals are reactive.
The most powerful oxidizing agents have a large positive oxidation potential and strong
reducing agents have a large negative potential.
11. Oxidation-Reduction Reactions:
Oxidation is the removal of electrons from an atom, and reduction is the addition of electrons
to an atom.
Corrosion and Galvanization
Galvanized iron is iron which has been coated with zinc to prevent rusting.
Consider the corrosion that may occur when a sheet of galvanized is scratched.
Standard potential and half cell reaction for both the metals
𝐹𝑒2+
+ 2𝑒 → 𝐹𝑒
𝑍𝑛2+
+ 2𝑒 → 𝑍𝑛
E⁰= -0.44 volts
E⁰= -0.76 volts
When in contact with water. either metal might be oxidized and lose metal ions, so we
require the reverse reactions, and the potentials for these are called oxidation potentials, and
have the same magnitude but the opposite sign to the reduction potentials.
12. Plainly, since Zn - Zn2+ produces the largest positive E⁰ value, and since
ΔG = -nFE⁰
it will produce the largest negative ΔG value. Thus it is energetically more favourable for the
Zn to dissolve, and hence the Zn will corrode away in preference to the Fe.
It is possible that when the galvanized steel is scratched, the air may oxidize some iron. The
Fe2+ so produced is immediately reduced to iron by the zinc, and rusting does not occur.
Thus the coating of zinc serves two purposes - first it covers the iron and prevents its
oxidation (rather like a coat of paint) and second it provides anodic protection. ·
• What species will oxidize or reduce.
• It gives an idea about the stability of oxidation state with respect to solvent.
• It suggests the possibility of disproportionation.
13. A great-deal of useful information about an element can be shown by the appropriate half
reactions and reduction potentials. Consider some half reactions involving iron:
Fe (VI), Fe(III), Fe(II), Fe(0)
Materials which are generally accepted as oxidizing agents have E⁰ values above +0.8 volts,
those such as Fe3+→Fe2+ of about 0.8 volts are stable (equally oxidizing and reducing), and
those below +0.8 volts become increasingly reducing.
14. 𝐹𝑒3+ + 𝑒 → 𝐹𝑒2+
E⁰= +0.77 volts
𝐹𝑒2+
+ 2𝑒 → 𝐹𝑒 E⁰= -0.47 volts
ΔG = -1 (+0.77)F = -0.77F
ΔG = -2 (-0.47)F = +0.94F
𝐹𝑒3+
+ 3𝑒 → 𝐹𝑒
ΔG = +0.17F
Now we can calculate E⁰ using the formula for Gibb‟s free energy
∆𝐺 = −𝑛𝐹𝐸0
𝐸0
= −
∆𝐺
𝑛𝐹
= −
0.17𝐹
3𝐹
= −0.057𝑉
15. One of the most important facts which can be obtained from a reduction potential diagram is
whether any of the oxidation states are unstable with regard to disproportionation.
Disproportionation is where one oxidation state decomposes, forming some ions in a higher
oxidation state, and some in a lower oxidation state. This happens when a given oxidation
state is a stronger oxidizing agent than the next highest oxidation state and this situation
occurs when a reduction potential on the right is more positive than one on the left.
𝐶𝑢+ + 𝑒 → 𝐶𝑢 E⁰= +0.50volts
𝐶𝑢+
→ 𝐶𝑢2+
+ 𝑒 E⁰= -0.15volts
ΔG = -1 (+0.50)F = -0.50F
ΔG = -1 (-0.15)F = +0.15F
2𝐶𝑢+ → 𝐶𝑢 + 𝐶𝑢2+ ΔG = -0.35F
Example1:
+0.35
16. Now we can calculate E⁰ using the formula for Gibb‟s free energy
∆𝐺 = −𝑛𝐹𝐸0
𝐸0 = −
∆𝐺
𝑛𝐹
= −
−0.35𝐹
𝐹
= +0.35𝑉
Example2:
+IV
+V
+VI +III 0
+IV
+V
+VI +III 0
1.74V
1.726V
18. The lattice energy ( U) of a crystal is the energy evolved when one gram molecule of the crystal
is formed from gaseous ions.
Lattice energy is defined as the energy required to separate a mole of an ionic solid into
gaseous ions.
Lattice energy cannot be measured empirically, but it can be calculated using electrostatics or
estimated using the Born-Haber cycle.
Theoretical values for lattice energy may be calculated. The ions are treated as point charges,
and the electrostatic ( coulombic) energy E between two ions of opposite charge is calculated:
𝐸 = −
𝑧+𝑧−𝑒2
𝑟
where
z+ and z- are the charges on the positive and negative ions
e is the charge on an electron
r is the inter-ionic distance
19. For more than two ions the electrostatic energy depends on the number of ions and also on A
their arrangement in space. For one mole the attractive energy is:
𝐸 = −
𝑁0𝐴𝑧+𝑧−𝑒2
𝑟
N₀is the Avogadro constant - the number of molecules in a mole. Which has the value 6. 023 ×
1023 mol-1
A is the Madelung constant, which depends on the geometry of the crystal.
20. • When the inter-ionic distance becomes small enough for the ions to touch, they begin to
repel each other. This repulsion originates from the mutual repulsion of the electron clouds
on the two atoms or ions.
• The repulsive forces increase rapidly as r decreases. The repulsive force is given by B/rn
where B is a constant that depends on the structure, an n is a constant called the Born
exponent. For one gram molecule the total repulsive force is (N0 B)/rn. The Born exponent
may be determined from compressibility measurements.
• The Born exponent value varies from 5-12, however chemists use a value of 9.
The total energy holding the crystal together is U the lattice energy. This is the sum of the
attractive and the repulsive forces.
𝑈 = −
𝑁0𝐴𝑧+𝑧−𝑒2
𝑟
+
𝑁0𝐵
𝑟𝑛
Attractive forces Repulsive forces
(A is the Madelung constant and B is a repulsion coefficient, which is constant which is
approximately proportional to the number of nearest neighbours.)
21. The equilibrium distance between ions is determined by the balance between the attractive and
repulsion terms. At equilibrium, dU/dr = 0, and the equilibrium distance r = r₀
𝑑𝑈
𝑑𝑟
=
𝑁0𝐴𝑧+𝑧−𝑒2
𝑟₀2
−
𝑛𝑁0𝐵
𝑟₀𝑛+1
= 0
Rearranging this gives an equation for the repulsion coefficient B.
Substituting the value of B in the formula for lattice energy
𝑈 = −
𝑁0𝐴𝑧+
𝑧−
𝑒2
𝑟₀
1 −
1
𝑛
This equation is called the Born-Lande equation. It allows the lattice energy to be
calculated from a knowledge of the geometry of the crystal, and hence the Madelung
constant, the charges z+ and z-, and the interionic distance.
When using. SI units, the equation takes the form:
𝑈 = −
𝑁0𝐴𝑧+
𝑧−
𝑒2
4𝜋𝜀₀𝑟₀
1 −
1
𝑛
where e₀ is the permittivity of free space = 8.854 x 10-12 Fm -1
22. Factors affecting Lattice Energy:
The lattice becomes stronger (i.e. the lattice energy U becomes more negative), as r the
interionic distance decreases. U is proportional to 1/r.
The lattice energy depends on the product of the ionic charges, and U is proportional to (z+
. z-).
There are two opposing factors in the equation. Increasing the inter-ionic distance r reduces
the lattice energy. It is .almost impossible to change r without changing the structure, and
therefore changing the Madelung constant A. Increasing A increases the lattice energy:
hence the· effects of changing rand A may largely cancel each other.
23. For a change of coordination number from 6 (NaCl structure} to 8 (CsCl structure) the inter-
ionic distance increases by 3.7%, and the Madelung constants (NaCl A = 1.74756, and CsCl A
= 1.76267) change by only 0. 9% . Thus a change in coordination number from 6 to 8 would
result in a reduction in lattice energy, and in theory the NaCl structure should always be more
stable than the CsCI structure. In a similar way reducing the coordination number from 6 to 4
decreases r by 4.9%. The decrease in A is 6.1% or 6.3% (depending on whether a zinc blende
or wurtzite structure is formed), but in either case it more than compensates for the change in r,
and in theory coordination number 6 is more stable than 4.
Reference:
1.Basic Inorganic Chemistry, F. A Cotton, G. Wilkinson, and Paul L. Gaus, 3rd
Edition (1995), John Wiley & Sons, New York.
2.Concise Inorganic Chemistry, J. D. Lee, 5th Edition (1996), Chapman & Hall, London.