Structures and bonding, properties of materials, quantitative chemistry and rates of reaction are discussed. Key topics covered include atomic structure, ionic and covalent bonding, properties of materials like conductivity and melting points, amounts of substances and moles, balancing chemical equations, factors that affect rates of reaction like temperature, concentration and surface area. The document provides an overview of content to be covered in additional science chapters on these core chemistry concepts.
All you need_to_know_about_additional_science[2]mcconvillezoe
This document provides an overview of additional science topics including atomic structure, bonding, properties of materials, quantitative chemistry concepts like moles and reacting masses, rates of reaction influenced by factors like concentration and catalysts, energy changes in reactions, electrolysis and information about acids, bases, salts and their reactions. It includes chapter outlines, explanations of concepts, diagrams and examples to illustrate essential ideas in chemistry.
The document discusses the electron configuration of noble gases and other elements. It explains that noble gases achieve a stable electron configuration of either a duplet or octet, while other elements must bond with each other to reach stability by donating, accepting, or sharing electrons. This bonding can occur through ionic bonds, where electrons are transferred, or covalent bonds, where electrons are shared. Ionic bonding results in the formation of ionic compounds between metals and nonmetals, while covalent bonding forms covalent compounds between nonmetals.
IB Chemistry on Resonance, Delocalization and Formal ChargesLawrence kok
The document discusses formal charge (FC) as a tool for determining the most acceptable Lewis structure. FC treats covalent bonds as having equal electron distribution and assigns a negative charge to more electronegative atoms and positive charge to less electronegative atoms. Examples of calculating FC for molecules like CO2, SO2, and ions are provided. Resonance structures are also discussed as describing electron delocalization in molecules that cannot be represented by a single Lewis structure.
1. Electronegativity is a measure of an atom's attraction for electrons in a covalent bond, measured on the Pauling scale from 0-4. Non-metals are more electronegative than metals, and electronegativity increases across and down a period.
2. Covalent and ionic bonding exist on a spectrum from purely ionic to purely covalent. The percentage of each can be estimated from the electronegativity difference between atoms using a provided table.
3. In polar covalent bonds, electrons are unequally shared due to differing electronegativities. This gives the atoms partial charges and an overall molecular dipole moment that increases with charge separation.
This document provides examples of electrochemistry questions and strategies for solving them. It addresses topics like predicting cell potentials, determining redox reactions, and identifying which species will be oxidized or reduced in different conditions. The examples demonstrate how to approach electrochemistry problems by writing out relevant half reactions and using standard reduction potentials.
This document provides an overview of chemical bonding and the properties of ionic and covalent compounds. It discusses the following key points:
1. Chemical bonds form due to the attraction between atoms and involve the transfer or sharing of valence electrons. Ionic bonds form through electron transfer between metals and nonmetals, while covalent bonds involve electron sharing.
2. Lewis symbols represent atoms and their valence electrons and are used to predict bonding patterns. Electronegativity determines bond polarity.
3. Ionic compounds have high melting and boiling points due to strong electrostatic attractions in the crystal lattice. Covalent compounds can be solids, liquids or gases.
This document discusses lattice energy and related concepts:
1) It defines lattice energy as the enthalpy change when one mole of an ionic solid forms from its gaseous ions, and explains how it depends on ion charge and radius.
2) Born-Haber cycles allow calculation of lattice energy by considering standard enthalpy changes in the step-wise formation of an ionic solid from its elements.
3) Ion polarization occurs when cation charge density and anion size lead to distortion of the anion electron cloud, influencing thermal stability.
The document provides instructions for students to complete a packet on chemical bonding, including drawing Lewis dot diagrams and determining bond type using electronegativity values. Students are asked to draw Bohr models and complete notes up to page 6 for homework. Materials and scheduling for assessments are also included.
All you need_to_know_about_additional_science[2]mcconvillezoe
This document provides an overview of additional science topics including atomic structure, bonding, properties of materials, quantitative chemistry concepts like moles and reacting masses, rates of reaction influenced by factors like concentration and catalysts, energy changes in reactions, electrolysis and information about acids, bases, salts and their reactions. It includes chapter outlines, explanations of concepts, diagrams and examples to illustrate essential ideas in chemistry.
The document discusses the electron configuration of noble gases and other elements. It explains that noble gases achieve a stable electron configuration of either a duplet or octet, while other elements must bond with each other to reach stability by donating, accepting, or sharing electrons. This bonding can occur through ionic bonds, where electrons are transferred, or covalent bonds, where electrons are shared. Ionic bonding results in the formation of ionic compounds between metals and nonmetals, while covalent bonding forms covalent compounds between nonmetals.
IB Chemistry on Resonance, Delocalization and Formal ChargesLawrence kok
The document discusses formal charge (FC) as a tool for determining the most acceptable Lewis structure. FC treats covalent bonds as having equal electron distribution and assigns a negative charge to more electronegative atoms and positive charge to less electronegative atoms. Examples of calculating FC for molecules like CO2, SO2, and ions are provided. Resonance structures are also discussed as describing electron delocalization in molecules that cannot be represented by a single Lewis structure.
1. Electronegativity is a measure of an atom's attraction for electrons in a covalent bond, measured on the Pauling scale from 0-4. Non-metals are more electronegative than metals, and electronegativity increases across and down a period.
2. Covalent and ionic bonding exist on a spectrum from purely ionic to purely covalent. The percentage of each can be estimated from the electronegativity difference between atoms using a provided table.
3. In polar covalent bonds, electrons are unequally shared due to differing electronegativities. This gives the atoms partial charges and an overall molecular dipole moment that increases with charge separation.
This document provides examples of electrochemistry questions and strategies for solving them. It addresses topics like predicting cell potentials, determining redox reactions, and identifying which species will be oxidized or reduced in different conditions. The examples demonstrate how to approach electrochemistry problems by writing out relevant half reactions and using standard reduction potentials.
This document provides an overview of chemical bonding and the properties of ionic and covalent compounds. It discusses the following key points:
1. Chemical bonds form due to the attraction between atoms and involve the transfer or sharing of valence electrons. Ionic bonds form through electron transfer between metals and nonmetals, while covalent bonds involve electron sharing.
2. Lewis symbols represent atoms and their valence electrons and are used to predict bonding patterns. Electronegativity determines bond polarity.
3. Ionic compounds have high melting and boiling points due to strong electrostatic attractions in the crystal lattice. Covalent compounds can be solids, liquids or gases.
This document discusses lattice energy and related concepts:
1) It defines lattice energy as the enthalpy change when one mole of an ionic solid forms from its gaseous ions, and explains how it depends on ion charge and radius.
2) Born-Haber cycles allow calculation of lattice energy by considering standard enthalpy changes in the step-wise formation of an ionic solid from its elements.
3) Ion polarization occurs when cation charge density and anion size lead to distortion of the anion electron cloud, influencing thermal stability.
The document provides instructions for students to complete a packet on chemical bonding, including drawing Lewis dot diagrams and determining bond type using electronegativity values. Students are asked to draw Bohr models and complete notes up to page 6 for homework. Materials and scheduling for assessments are also included.
Chemistry is the study of matter and its changes. An atom is the smallest particle of an element that retains the properties of that element. Atoms combine to form compounds with fixed ratios. A chemical change alters the composition of a substance, while a physical change does not. The atomic theory states that elements are composed of atoms and compounds are composed of two or more different elements chemically bonded. The structure of the atom consists of a small, dense nucleus surrounded by electrons. Chemical formulas represent the elements and their ratios in compounds and molecules. Ions are formed when atoms gain or lose electrons. Naming and formulas help identify substances. Acids donate hydrogen ions in water and bases donate hydroxide ions.
The document summarizes key aspects of the periodic table, including:
1) It describes the historical development of the periodic table by scientists like Lavoisier, Dobereiner, Newlands, Meyer, and Mendeleev.
2) It explains the modern arrangement of elements in the periodic table based on proton number and discusses the properties of elements in the same group and period.
3) It provides examples of properties and reactions of representative elements from groups 1, 17, 18 and period 3 of the periodic table. Transition elements and semimetals are also discussed.
1) Noble gases do not form ions or bonds because they have a stable octet of electrons, matching the configuration of the nearest noble gas.
2) Atoms form ions to achieve a stable octet. Metals form cations by losing electrons, nonmetals form anions by gaining electrons.
3) Ionic compounds consist of positively and negatively charged ions with an overall neutral charge. The formula shows the ratio of cations to anions needed for charge balance.
IB Chemistry on Allotrope, Alloy, Graphene and crystalline structureLawrence kok
The document discusses different allotropes of carbon including diamond, fullerene (C60), graphene, and graphite. It provides details on their molecular structures, bonding, and properties. Diamond has a giant covalent structure and is the hardest known material. Fullerene has 60 carbon atoms arranged in a hollow spherical shape. Graphene is a single layer of sp2 hybridized carbon atoms arranged in a hexagonal honeycomb lattice. Graphite consists of layers of graphene held together by weak van der Waals forces between the layers. It is a good lubricant and widely used in pencils and electrodes.
The document outlines key concepts in electrochemistry including:
1. Electrolysis involves using electricity to break down ionic compounds or solutions into their components. It occurs when ions are able to move freely in molten or aqueous states.
2. During electrolysis, cations move to the cathode where they gain electrons and undergo reduction reactions. Anions move to the anode where they lose electrons and undergo oxidation reactions.
3. The electrolysis of molten ionic compounds produces metals at the cathode and non-metals at the anode. Electrolysis of aqueous solutions can produce hydrogen and oxygen from water or discharge other ions depending on their reactivity.
FREE RADICALS , CARBENES AND NITRENES.pptxtenzinpalmo3
This document discusses free radicals, carbenes, and nitrenes. It defines each type of species, describes their characteristics such as electronic structure and stability. The document outlines different types for each species and methods for their formation and synthetic applications. Free radicals form through bond homolysis and vary in stability based on alkyl substituents. Carbenes are divalent carbon species that exist as singlet or triplet forms with different hybridizations. Nitrenes are analogous to carbenes but with nitrogen and vary in stability and spin state. Examples of formation and trapping methods are provided along with sample synthetic reactions for each reactive intermediate.
IB Chemistry on Polarity, Hydrogen Bonding and Van Der Waals forcesLawrence kok
This document provides a tutorial on chemical bonding including ionic bonds, covalent bonds, polarity, hydrogen bonding, and intermolecular forces. It discusses how ionic bonds form through the transfer of electrons between metals and nonmetals, and how covalent bonds form through the sharing of electrons between nonmetals. It also explains how polarity arises from unequal sharing of electrons and differences in electronegativity. Additional concepts covered include London dispersion forces, dipole-dipole interactions, factors that influence boiling points, and the properties of hydrogen bonding.
1. Electrochemistry involves redox reactions where one element is oxidized and another is reduced. Oxidation is the loss of electrons and an increase in oxidation number, while reduction is the gain of electrons and a decrease in oxidation number.
2. Electrolysis is the passage of an electric current through an ionic substance to cause a non-spontaneous redox reaction. Oxidation occurs at the anode and reduction at the cathode.
3. Aluminum is extracted from bauxite via electrolysis. Bauxite is dissolved in molten cryolite to lower its melting point, then electrolysis separates aluminum ions at the cathode.
CONTENTS
Electrochemistry: definition & importance
Conductors: metallic & electrolytic conduction,
Electrolytes, Electrochemical cell & electrolytic cell
A simple electrochemical cell: Galvanic cell or (Daniell Cell)
Cell reaction, cell representation, Salt bridge & its use,
Electrode potential, standard electrode potential, SHE,
Standard cell potential or standard electromotive force of a cell
Electrochemical series (Standard reduction potential values)
Nernst Equation, Relationship with Standard cell potential with Gibbs energy & also equilibrium constant
Resistance (R) & conductance (G) of a solution of an electrolyte
Conductivity (k) of solution, Cell constant (G*) & their units,
Molar conductivity (Λm) & its variation with concentration & temperature,
Debye Huckel Onsager equation & Limiting molar conductivity,
Kohlrausch’s law & its application & numerical problems.
Electrolytic cells & electrolysis.
Some examples of electrolysis of electrolytes in molten / aq. state.
Faraday’s laws of electrolysis: First & second law- numerical problems. Corrosion, Electrochemical theory of rusting.
Prevention of rusting.
This document provides an overview of electrochemistry and voltaic cells. It discusses redox reactions, how to balance redox reactions using the half-reaction method, and the components and operation of voltaic cells. Specifically, it explains that a voltaic cell uses a spontaneous redox reaction to generate electrical energy by separating the oxidation and reduction half-reactions into two half-cells connected by an external circuit and salt bridge. Electrons flow from the anode, where oxidation occurs, through the external circuit to the cathode, where reduction occurs.
This document provides an outline for a lesson on transition metals and complex ions. It includes:
1) A review of trends in the d-block elements from Topic 3.
2) An explanation of what defines a transition metal and their common properties.
3) A discussion of how transition metals can form complex ions with variable oxidation states and an investigation of complex ions.
4) An explanation of why complex ions are often colored due to d-orbital splitting effects.
The document discusses electrochemistry and electrolysis. It defines electrolytes and non-electrolytes, and explains how electrolytes can conduct electricity in molten or aqueous states through the movement of ions. Examples are given of electrolysis processes and how electrolysis can be used for metal extraction, purification, and electroplating.
Electrolysis is the decomposition of a substance by an electric current, where electrolytes carry current as ions in solution. During electrolysis, ions move to the electrodes and undergo oxidation or reduction reactions. At the cathode, electrons are gained and reduction occurs. At the anode, electrons are lost and oxidation occurs. The amount of substance deposited or gas produced can be calculated using Faraday's law, relating current, time, and moles of electrons in the electrode reactions.
This document discusses electrochemistry and voltaic cells. It begins by defining electrochemistry as the interconversion of chemical and electrical energy. It then discusses electrolysis and voltaic cells. Electrolysis involves using electricity to break down substances, while voltaic cells convert chemical energy to electrical energy. The document goes on to describe the components and reactions of voltaic cells, including simple voltaic cells and Daniell cells. It also discusses applications of electrolysis in industries such as metal extraction and electroplating.
1) The document discusses atomic structure and bonding, covering the history of atomic theory from Dalton to Chadwick. It describes the structure of atoms including protons, neutrons and electrons.
2) Atomic number and mass are defined, and electron configuration is explained using quantum numbers. Different types of chemical bonds are covered - ionic formed by electron transfer, covalent by electron sharing, and metallic by delocalized electrons.
3) Secondary bonds such as hydrogen and van der Waals bonds are also summarized. The periodic table is shown organizing elements by electron configuration. Different classes of elements - metals, nonmetals and metalloids - are defined by their bonding properties.
This document discusses key concepts in electrochemistry including electrode potentials, galvanic cells, and electrolytic cells. It defines electrode potentials as the electric potential arising from the separation of charges in redox half reactions. Standard electrode potentials can be measured versus the standard hydrogen electrode and indicate whether the forward or backward reaction is favored. Electrode potentials are also used to predict the feasibility of redox reactions. The document distinguishes anodes and cathodes in galvanic and electrolytic cells and how to draw cell diagrams. It provides strategies for using calculations involving current, time, moles of electrons, and Faraday's constant to solve electrochemistry problems.
IB Chemistry on Resonance, Delocalization and Ozone DestructionLawrence kok
1) Ozone (O3) has a bond order of 1.5, with bond lengths intermediate between single and double bonds. Its structure is a resonance hybrid of two contributing resonance structures.
2) Ozone in the stratosphere absorbs harmful UV-B and UV-C radiation from the sun, protecting life on Earth. However, ozone in the troposphere is a air pollutant.
3) Chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) can reach the stratosphere where they are broken down by UV radiation, releasing chlorine radicals that catalytically destroy ozone.
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.
e RT
Where;
D0 = Diffusion coefficient at infinite temperature
Q = Activation energy for diffusion
R = Gas constant
T = Absolute temperature
This chapter discusses imperfections in crystals and solidification processes. There are several types of imperfections including point defects like vacancies and interstitial atoms, and line defects like dislocations. Solidification involves nucleation of stable nuclei from liquid, growth of these nuclei into a grain structure, and formation of grain boundaries. Single crystals can be grown using the Czochralski process by slowly pulling a seed crystal from a melt. Diffusion, which is temperature dependent, allows for solid state reactions and involves either vacancy or interstitial mechanisms.
Agritool è un prodotto innovativo realizzato per le aziende agricole che vogliono un controllo continuo e aggiornato dei fattori di produzione.
È uno strumento pensato per far emergere potenzialità, per migliorare e diversificare le fonti di reddito, per stimolare l’imprenditorialità sviluppando un nuovo modo di intendere l’impresa agricola italiana.
Chemistry is the study of matter and its changes. An atom is the smallest particle of an element that retains the properties of that element. Atoms combine to form compounds with fixed ratios. A chemical change alters the composition of a substance, while a physical change does not. The atomic theory states that elements are composed of atoms and compounds are composed of two or more different elements chemically bonded. The structure of the atom consists of a small, dense nucleus surrounded by electrons. Chemical formulas represent the elements and their ratios in compounds and molecules. Ions are formed when atoms gain or lose electrons. Naming and formulas help identify substances. Acids donate hydrogen ions in water and bases donate hydroxide ions.
The document summarizes key aspects of the periodic table, including:
1) It describes the historical development of the periodic table by scientists like Lavoisier, Dobereiner, Newlands, Meyer, and Mendeleev.
2) It explains the modern arrangement of elements in the periodic table based on proton number and discusses the properties of elements in the same group and period.
3) It provides examples of properties and reactions of representative elements from groups 1, 17, 18 and period 3 of the periodic table. Transition elements and semimetals are also discussed.
1) Noble gases do not form ions or bonds because they have a stable octet of electrons, matching the configuration of the nearest noble gas.
2) Atoms form ions to achieve a stable octet. Metals form cations by losing electrons, nonmetals form anions by gaining electrons.
3) Ionic compounds consist of positively and negatively charged ions with an overall neutral charge. The formula shows the ratio of cations to anions needed for charge balance.
IB Chemistry on Allotrope, Alloy, Graphene and crystalline structureLawrence kok
The document discusses different allotropes of carbon including diamond, fullerene (C60), graphene, and graphite. It provides details on their molecular structures, bonding, and properties. Diamond has a giant covalent structure and is the hardest known material. Fullerene has 60 carbon atoms arranged in a hollow spherical shape. Graphene is a single layer of sp2 hybridized carbon atoms arranged in a hexagonal honeycomb lattice. Graphite consists of layers of graphene held together by weak van der Waals forces between the layers. It is a good lubricant and widely used in pencils and electrodes.
The document outlines key concepts in electrochemistry including:
1. Electrolysis involves using electricity to break down ionic compounds or solutions into their components. It occurs when ions are able to move freely in molten or aqueous states.
2. During electrolysis, cations move to the cathode where they gain electrons and undergo reduction reactions. Anions move to the anode where they lose electrons and undergo oxidation reactions.
3. The electrolysis of molten ionic compounds produces metals at the cathode and non-metals at the anode. Electrolysis of aqueous solutions can produce hydrogen and oxygen from water or discharge other ions depending on their reactivity.
FREE RADICALS , CARBENES AND NITRENES.pptxtenzinpalmo3
This document discusses free radicals, carbenes, and nitrenes. It defines each type of species, describes their characteristics such as electronic structure and stability. The document outlines different types for each species and methods for their formation and synthetic applications. Free radicals form through bond homolysis and vary in stability based on alkyl substituents. Carbenes are divalent carbon species that exist as singlet or triplet forms with different hybridizations. Nitrenes are analogous to carbenes but with nitrogen and vary in stability and spin state. Examples of formation and trapping methods are provided along with sample synthetic reactions for each reactive intermediate.
IB Chemistry on Polarity, Hydrogen Bonding and Van Der Waals forcesLawrence kok
This document provides a tutorial on chemical bonding including ionic bonds, covalent bonds, polarity, hydrogen bonding, and intermolecular forces. It discusses how ionic bonds form through the transfer of electrons between metals and nonmetals, and how covalent bonds form through the sharing of electrons between nonmetals. It also explains how polarity arises from unequal sharing of electrons and differences in electronegativity. Additional concepts covered include London dispersion forces, dipole-dipole interactions, factors that influence boiling points, and the properties of hydrogen bonding.
1. Electrochemistry involves redox reactions where one element is oxidized and another is reduced. Oxidation is the loss of electrons and an increase in oxidation number, while reduction is the gain of electrons and a decrease in oxidation number.
2. Electrolysis is the passage of an electric current through an ionic substance to cause a non-spontaneous redox reaction. Oxidation occurs at the anode and reduction at the cathode.
3. Aluminum is extracted from bauxite via electrolysis. Bauxite is dissolved in molten cryolite to lower its melting point, then electrolysis separates aluminum ions at the cathode.
CONTENTS
Electrochemistry: definition & importance
Conductors: metallic & electrolytic conduction,
Electrolytes, Electrochemical cell & electrolytic cell
A simple electrochemical cell: Galvanic cell or (Daniell Cell)
Cell reaction, cell representation, Salt bridge & its use,
Electrode potential, standard electrode potential, SHE,
Standard cell potential or standard electromotive force of a cell
Electrochemical series (Standard reduction potential values)
Nernst Equation, Relationship with Standard cell potential with Gibbs energy & also equilibrium constant
Resistance (R) & conductance (G) of a solution of an electrolyte
Conductivity (k) of solution, Cell constant (G*) & their units,
Molar conductivity (Λm) & its variation with concentration & temperature,
Debye Huckel Onsager equation & Limiting molar conductivity,
Kohlrausch’s law & its application & numerical problems.
Electrolytic cells & electrolysis.
Some examples of electrolysis of electrolytes in molten / aq. state.
Faraday’s laws of electrolysis: First & second law- numerical problems. Corrosion, Electrochemical theory of rusting.
Prevention of rusting.
This document provides an overview of electrochemistry and voltaic cells. It discusses redox reactions, how to balance redox reactions using the half-reaction method, and the components and operation of voltaic cells. Specifically, it explains that a voltaic cell uses a spontaneous redox reaction to generate electrical energy by separating the oxidation and reduction half-reactions into two half-cells connected by an external circuit and salt bridge. Electrons flow from the anode, where oxidation occurs, through the external circuit to the cathode, where reduction occurs.
This document provides an outline for a lesson on transition metals and complex ions. It includes:
1) A review of trends in the d-block elements from Topic 3.
2) An explanation of what defines a transition metal and their common properties.
3) A discussion of how transition metals can form complex ions with variable oxidation states and an investigation of complex ions.
4) An explanation of why complex ions are often colored due to d-orbital splitting effects.
The document discusses electrochemistry and electrolysis. It defines electrolytes and non-electrolytes, and explains how electrolytes can conduct electricity in molten or aqueous states through the movement of ions. Examples are given of electrolysis processes and how electrolysis can be used for metal extraction, purification, and electroplating.
Electrolysis is the decomposition of a substance by an electric current, where electrolytes carry current as ions in solution. During electrolysis, ions move to the electrodes and undergo oxidation or reduction reactions. At the cathode, electrons are gained and reduction occurs. At the anode, electrons are lost and oxidation occurs. The amount of substance deposited or gas produced can be calculated using Faraday's law, relating current, time, and moles of electrons in the electrode reactions.
This document discusses electrochemistry and voltaic cells. It begins by defining electrochemistry as the interconversion of chemical and electrical energy. It then discusses electrolysis and voltaic cells. Electrolysis involves using electricity to break down substances, while voltaic cells convert chemical energy to electrical energy. The document goes on to describe the components and reactions of voltaic cells, including simple voltaic cells and Daniell cells. It also discusses applications of electrolysis in industries such as metal extraction and electroplating.
1) The document discusses atomic structure and bonding, covering the history of atomic theory from Dalton to Chadwick. It describes the structure of atoms including protons, neutrons and electrons.
2) Atomic number and mass are defined, and electron configuration is explained using quantum numbers. Different types of chemical bonds are covered - ionic formed by electron transfer, covalent by electron sharing, and metallic by delocalized electrons.
3) Secondary bonds such as hydrogen and van der Waals bonds are also summarized. The periodic table is shown organizing elements by electron configuration. Different classes of elements - metals, nonmetals and metalloids - are defined by their bonding properties.
This document discusses key concepts in electrochemistry including electrode potentials, galvanic cells, and electrolytic cells. It defines electrode potentials as the electric potential arising from the separation of charges in redox half reactions. Standard electrode potentials can be measured versus the standard hydrogen electrode and indicate whether the forward or backward reaction is favored. Electrode potentials are also used to predict the feasibility of redox reactions. The document distinguishes anodes and cathodes in galvanic and electrolytic cells and how to draw cell diagrams. It provides strategies for using calculations involving current, time, moles of electrons, and Faraday's constant to solve electrochemistry problems.
IB Chemistry on Resonance, Delocalization and Ozone DestructionLawrence kok
1) Ozone (O3) has a bond order of 1.5, with bond lengths intermediate between single and double bonds. Its structure is a resonance hybrid of two contributing resonance structures.
2) Ozone in the stratosphere absorbs harmful UV-B and UV-C radiation from the sun, protecting life on Earth. However, ozone in the troposphere is a air pollutant.
3) Chlorofluorocarbons (CFCs) and other ozone-depleting substances (ODS) can reach the stratosphere where they are broken down by UV radiation, releasing chlorine radicals that catalytically destroy ozone.
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.
e RT
Where;
D0 = Diffusion coefficient at infinite temperature
Q = Activation energy for diffusion
R = Gas constant
T = Absolute temperature
This chapter discusses imperfections in crystals and solidification processes. There are several types of imperfections including point defects like vacancies and interstitial atoms, and line defects like dislocations. Solidification involves nucleation of stable nuclei from liquid, growth of these nuclei into a grain structure, and formation of grain boundaries. Single crystals can be grown using the Czochralski process by slowly pulling a seed crystal from a melt. Diffusion, which is temperature dependent, allows for solid state reactions and involves either vacancy or interstitial mechanisms.
Agritool è un prodotto innovativo realizzato per le aziende agricole che vogliono un controllo continuo e aggiornato dei fattori di produzione.
È uno strumento pensato per far emergere potenzialità, per migliorare e diversificare le fonti di reddito, per stimolare l’imprenditorialità sviluppando un nuovo modo di intendere l’impresa agricola italiana.
This document discusses penetration testing of VoIP networks using the Viproy VoIP penetration testing kit. It begins with an introduction of the author and his background in VoIP security. It then demonstrates the Viproy kit in action and discusses basic attacks against SIP services like discovery, footprinting, and spoofing calls. It also covers more advanced attacks like the SIP proxy bounce attack, creating fake services to perform man-in-the-middle attacks, distributed denial of service attacks, and exploiting trust relationships between SIP gateways. The document concludes by discussing fuzzing SIP services and clients to find vulnerabilities.
This document discusses security vulnerabilities in hosted VoIP environments. It summarizes techniques for attacking Cisco phones and VoIP infrastructure, including spoofing caller ID, manipulating SIP trust relationships, and escalating privileges on Cisco Unified Communications Manager and VOSS Domain Manager services. The document outlines methods for gaining persistent access to networks and manipulating call forwarding, speed dials and other phone settings.
The Art of VoIP Hacking - Defcon 23 WorkshopFatih Ozavci
VoIP attacks have evolved, and they are targeting Unified Communications (UC), commercial services, hosted environment and call centres using major vendor and protocol vulnerabilities. This workshop is designed to demonstrate these cutting edge VoIP attacks, and improve the VoIP skills of the incident response teams, penetration testers and network engineers. Signalling protocols are the centre of UC environments, but also susceptible to IP spoofing, trust issues, call spoofing, authentication bypass and invalid signalling flows. They can be hacked with legacy techniques, but a set of new attacks will be demonstrated in this workshop. This workshop includes basic attack types for UC infrastructure, advanced attacks to the SIP and Skinny protocol weaknesses, network infrastructure attacks, value added services analysis, Cdr/Log/Billing analysis and Viproy use to analyse signalling services using novel techniques. Also the well-known attacks to the network infrastructure will be combined with the current VoIP vulnerabilities to test the target workshop network. Attacking VoIP services requires limited knowledge today with the Viproy Penetration Testing Kit (written by Fatih). It has a dozen modules to test trust hacking issues, information collected from SIP and Skinny services, gaining unauthorised access, call redirection, call spoofing, brute-forcing VoIP accounts, Cisco CUCDM exploitation and debugging services using as MITM. Furthermore, Viproy provides these attack modules in the Metasploit Framework environment with full integration. The workshop contains live demonstration of practical VoIP attacks and usage of the Viproy modules.
In this hands-on workshop, attendees will learn about basic attack types for UC infrastructure, advanced attacks to the SIP protocol weaknesses, Cisco Skinny protocol hacking, hacking Cisco CUCDM and CUCM servers, network infrastructure attacks, value added services analysis, Cdr/Log/Billing analysis and Viproy VoIP pen-test kit to analyse VoIP services using novel techniques. New CDP, CUCDM and Cisco Skinny modules and techniques of Viproy will be demonstrated in the workshop as well.
The document provides instructions and materials for a chemistry lesson on chemical bonding, including ionic and covalent bonding, periodic tables, and practice questions to review electron configuration and bonding characteristics. Students are assigned roles such as materials manager and oral presenter for demonstrating a lesson on chemical bonding using video clips and examples of bonding in molecules like glucose and sucrose.
Electrons and Chemical Bonding Spring 2013 Day 2jmori
This document provides instructions and information for students regarding upcoming assignments, tests, and study materials. It includes the following key points:
1. Students are given instructions to complete assignments on building blocks of matter, test corrections, ionic and covalent bonding, and flashcards. Due dates are provided.
2. Information is provided on retaking a test, including the required score, date, and need for a parent signature.
3. Details are given on creating flashcards with questions on one side and answers on the other to study for an upcoming quiz.
4. Sample questions are provided to help students study key
Electrons and chemical bonding spring 2013 day 1jmori
The document provides instructions for students on materials and assignments needed for an upcoming chemistry lesson, including taking a retake test, making study cards with questions and answers, and instructions for new seating assignments and job roles for group work including manager, materials manager, timer designer and oral presenter.
Matter and materials (II) Paticles that substances are made up ofLily Kotze
Particles that substances are made up of can be atoms, molecules, or ions. Atoms are the basic building blocks of matter that combine to form elements or compounds. Elements are either monoatomic like hydrogen gas or diatomic like oxygen gas. Compounds contain two or more different elements combined in fixed proportions. The molecular, empirical, and structural formulas are used to represent compounds. Substances can have covalent, ionic, or metallic bonding that results in different macroscopic properties. Chemical and physical changes can be distinguished based on whether atoms are rearranged. Chemical reactions involve energy absorption or release as bonds are broken and formed.
This document provides an overview of basic chemistry concepts. It explains that all matter is made up of atoms, and atoms can combine to form either elements or compounds. The structure of the atom is described, including subatomic particles like protons, neutrons, and electrons. Electron configuration and chemical bonding via ionic and covalent bonds are also summarized. Key terms like isotopes, ions, the periodic table, and electronegativity are defined.
This document provides an overview of chemical bonding concepts covered in Chapter 6, including:
1) Valence electrons and how to determine them from the periodic table.
2) The main types of chemical bonds - ionic, covalent, and metallic. Ionic bonds form between metals and nonmetals, covalent between nonmetals, and metallic within metals.
3) Key characteristics of ionic and covalent bonds such as crystal structure, conductivity, and bond strength. Lewis structures are used to represent covalent bonds.
Rutherford's scattering experiment showed that the atom has a small, dense nucleus surrounded by electrons. Most alpha particles passed through the gold foil, but some were deflected or reflected, indicating a small, positively charged nucleus. The development of the atomic model over time led to the discovery of subatomic particles like protons, neutrons, and electrons. The periodic table arranges elements in order of atomic number and groups elements with similar properties together.
The document introduces the periodic table and discusses how it is organized. It explains that elements are arranged by atomic number vertically into groups and horizontally into periods. [The document] instructs the reader to draw electron configuration diagrams for the first 20 elements and observe that elements in the same group have the same number of valence electrons. It also notes that elements in the same period have the same number of electron shells. In conclusion, [the document] emphasizes that the number and arrangement of valence electrons determines how an element bonds and reacts chemically.
The document discusses the electron configuration of noble gases and other elements. It explains that noble gases achieve a stable electron configuration of either a duplet or octet, while other elements must gain, lose, or share electrons to also achieve stable configurations and form ionic or covalent bonds. It then provides examples of the formation of ionic compounds, such as sodium chloride and magnesium chloride, through the transfer of electrons between atoms to create ions that are then held together by electrostatic forces.
This document provides an overview of atomic structure and the development of atomic theory. It discusses the basic composition of atoms, including electrons, protons, and neutrons. It describes Dalton's atomic theory and the key postulates. It also discusses subatomic particles like isotopes, ions, and the discovery of electrons, protons, and neutrons through experiments. The document is divided into sections on the composition of atoms, atomic calculations, isotopes, ions, atomic mass, and the development of atomic theory from Dalton to the discovery of subatomic particles.
This document provides an overview of atomic bonding and properties. It discusses how the arrangement of atoms and interactions between atoms determine properties. The main types of bonds - ionic, covalent, and metallic - are introduced along with how they relate to properties like melting temperature and thermal expansion. Bonding concepts like bond energy, bond length, and the relationship between bonding strength and properties are explained through diagrams of bonding curves. The roles of factors like atomic radius, electronegativity, and bond type in determining properties are also summarized.
This document discusses bonding and properties in materials. It addresses what promotes bonding, the types of bonds, and properties inferred from bonding. The main types of bonds are ionic, covalent, and metallic. Ionic bonding occurs between ions and requires a large difference in electronegativity. Covalent bonding shares electrons between similar electronegativity atoms. Metallic bonding arises from delocalized valence electrons. Bonding type influences properties like melting temperature, elastic modulus, and thermal expansion.
1. Isotopes are atomic forms of the same element that have the same number of protons and electrons but a different number of neutrons.
2. Ionic bonding occurs when metals lose electrons to form positive ions, and non-metals gain electrons to form negative ions. Ionic compounds have high melting and boiling points.
3. Covalent bonding occurs when two non-metal atoms share electrons in their outer shell to complete their electron configuration. Covalent substances have low melting and boiling points.
1. Isotopes are atomic forms of the same element that have the same number of protons and electrons but a different number of neutrons.
2. Ionic bonding occurs when metals lose electrons to form positive ions, and non-metals gain electrons to form negative ions. Ionic compounds have high melting and boiling points.
3. Covalent bonding occurs when two non-metal atoms share electrons in their outer shell to complete their electron configuration. Covalent substances have low melting and boiling points.
The document discusses topics related to chemical reactions and the periodic table. It provides information on:
- Mendeleev's creation of the periodic table and how he arranged elements based on their properties.
- The structure of atoms consisting of protons, neutrons, and electrons located in electron shells around the nucleus.
- The modern periodic table including atomic number and mass number.
- Ionic bonding forming between metals and non-metals through the transfer of electrons. Ionic compounds have high melting/boiling points and conduct electricity when molten or dissolved.
- Covalent bonding forming when atoms share electrons in covalent molecules. Simple covalent substances have low melting/boiling points while giant
I. Ionic bonds form when an atom with high electronegativity steals an electron from a atom with low electronegativity, giving them partial charges that attract via electromagnetic force.
II. Covalent bonds form when two atoms share electrons equally. Polar covalent bonds occur when sharing is unequal, giving partial charges.
III. Bonding exists on a spectrum from full electron transfer in ionic bonds to equal sharing in covalent bonds. Metallic bonds involve metal ions stabilized by a "sea" of delocalized electrons.
The document discusses chemical bonding, including the formation of ions, ionic bonds, metallic bonds, and covalent bonds. Ions are formed when atoms gain or lose electrons to obtain full outer electron shells. Ionic bonds form when ions of opposite charge attract via electrostatic forces. Metallic bonds occur via delocalized electrons within metal atoms. Covalent bonds form through the sharing of electron pairs between nonmetal atoms. The octet rule and electronegativity help explain bonding properties.
The document provides information about the four fundamental forces and particles that make up everything in the universe:
1) Gravity and magnetism are the two forces that act on matter and charged particles respectively. Gravity always pulls while magnetism can pull or push.
2) All matter is made up of fundamental particles called protons, neutrons, and electrons that combine to form atoms. Protons and neutrons are found in the nucleus while electrons orbit around the nucleus.
3) Atoms can combine to form molecules, and everything in the universe from people to planets are made up of these fundamental forces and particles.
This document discusses ionic compounds and the formation of ionic bonds. Ions form when atoms gain or lose electrons to achieve stable electron configurations like noble gases. Ionic bonds occur between oppositely charged ions and result in crystalline solids with high melting points. The document explains how to name ionic compounds based on the cation and anion present and write chemical formulas from compound names. It also briefly discusses metallic bonding and the properties of metals and alloys.
Similar to All you need_to_know_about_additional_science[1] (20)
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
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.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
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.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
2. Chapters in this unit
• 1. Structures and bonding
• 2. Structures and properties
• 3. How much?
• 4. Rates of reaction
• 5. Energy and reactions
• 6. Electrolysis
• 7. Acids, alkalis and salts
3. 1.1 Atomic structure
Type of sub-atomic particle Relative charge Mass
Proton +1 1
Neutron 0 1
Electron -1 Negligible
4. 1.1 Atomic structure
Columns = groups
Group number = number of electrons in outer shell
Row number = number of shells
Rows = periods
5. 1.1 Atomic structure
Atomic Mass
number: number:
The The
number of number of
protons in protons
an atom and
neutrons
in an atom
6. 1.2 Electronic arrangement
Each shell =
different energy level
Shell nearest nucleus =
lowest energy level
Energy needed to
overcome attractive
forces between protons
and electrons
7. 1.2 Electronic arrangement
Group 1 metals (aka alkali metals)
- Have 1 electron in outer most shell
- Soft metals, easily cut
- Reacts with water and oxygen
- Reactivity increases down the group
- Low melting and boiling points
8. 1.2 Electronic arrangement
Group 0/8 metals (aka noble gases)
- Have 2/8 electrons in outer most shell
- Very stable gases, no reaction
10. 1.3 Chemical bonding
• Mixture
The combined substances do not change
Easy to separate
• Compound
Chemical reaction takes place
Bonds form between atoms
11. 1.4 Ionic bonding
(metal + non-metal)
Look! Look!
Group 1 element Group 7 element
Very strong forces of attraction between
positive and negative ions = ionic bond
12. 1.4 Ionic bonding
(metal + non-metal)
Ionic bonds form a giant lattice structure
15. 2.1 – 2.4 Properties
Ionic Simple Giant Metallic
(covalent) (covalent)
Melting point
intermolecular
electrostatic
bonds, weak
covalent
covalent
Strong
forces
Boiling point
Strong
Strong
forces
bonds
Electrical/ Yes, when No, due No – diamond Yes, due to
heat conductor molten or in to no overall Yes – delocalised
solution (aq) charge graphite electrons
as allows due to
ions to move delocalised
electrons
16. 2.3 Graphite
Layers of graphite slip off and leave a mark on paper
The free e- from each C atom can move in between
the layers, making graphite a good conductor of
electricity
17. 2.4 Metal
• Pure metals are made
up of layers of one
type of atoms
• These slide easily
over one another and
therefore metals can
be bent and shaped
18. 2.5 Nanoscience
• Structures are:
1-100 nm in size or
a few hundred atoms
• Show different properties to same materials
in bulk
• Have high surface area to volume ratio
19. 2.5 Nanoscience
• Titanium oxide on • Silver and socks
windows Silver nanoparticles
Titanium oxide in socks can prevent
reacts with sunshine, the fabric from
which breaks down smelling
dirt
20. 3.1 Mass numbers
Mass number – Isotopes
atomic number • Same number of protons
= number of neutrons • Different number of
neutrons
E.g. Sodium
23 – 11 = 12
21. 3.2 Masses of atoms and
moles
Relative atomic masses (Ar) Moles
Mass of atom compared to 12C • A mole of any substance
always contains same
e.g. Na = 23, Cl = 35.5 number of particles
Relative formula masses (Mr) - Relative atomic mass in
grams
Mass of a compound found by
adding Ar of each element
- Relative formula mass in
grams
e.g. NaCl = 23 + 35.5 = 58.5
22. 3.3 Percentages and formulae
Percentage mass
% = mass of element
total mass of compound
Percentage composition / empirical formula
Al Cl
Mass 9 35.5
Ar 27 35.5
Moles (9/27) = 0.33 (35.5/35.5) = 1
Simplest ratio (0.33 / 0.33) = 1 (1 / 0.33) = 3
(divide by smallest
number of moles)
Formula AlCl3
23. 3.4 Balancing equations
H2 + O2 H2O
Elements Elements
(Right-hand side) (Left-hand side)
H= H=
O= O=
24. 3.4 Reacting masses
2NaOH + Cl2 NaOCl + NaCl + H2O
If we have a solution containing 100 g of sodium
hydroxide, how much chlorine gas should we pass
through the solution to make bleach? Too much, and
some chlorine will be wasted, too little and not all of the
sodium hydroxide will react.
25. 3.4 Reacting masses
2NaOH + Cl2 NaOCl + NaCl + H2O
100 g ?
2NaOH Cl2
Ar / Mr 80 71
Ratio (80/80) = 1 (71/80) = 0.8875
1 x 100 = 100 0.8875 x 100 = 88.75
Mass 100 g 88.75 g
26. 3.5 Percentage yield
Very few chemical reactions have a yield of
100% because:
• Reaction is reversible
• Some reactants produce unexpected products
• Some products are left behind in apparatus
• Reactants may not be completely pure
• More than one product is produced and it may
be difficult to separate the product we want
28. 3.5 Atom economy
The amount of the starting materials that end
up as useful products is called the atom
economy
% atom economy = Mr of useful product x 100%
Mr of all products
30. 3.7 Haber process
• Fritz Haber invented
the Haber process
• A way of turning
nitrogen in the air
into ammonia
450oC
200 atm
N2 + 3H2 2NH3
31. 4.2 Collision theory
Collision theory Rate of reaction
Chemical reactions increases if:
only occur when • temperature
reacting particles increases
collide with each other • concentration or
with sufficient energy. pressure increases
The minimum amount • surface area
of energy is called the increases
activation energy
• catalyst used
32. 4.2 Surface area
Why?
The inside of a large piece of solid is not in
contact with the solution it is reacting with, so
it cannot react
How?
Chop up solid reactant into
smaller pieces or crush into
a powder
33. 4.3 Temperature
Why?
At lower temperatures, particles will collide:
a) less often
b) with less energy
How?
Put more energy into reaction
Increasing the temperature
by 10oC will double the rate
of reaction
34. 4.4 Concentration
Why?
Concentration is a measure of how many
particles are in a solution. Units = mol/dm3
The lower the concentration, the fewer
reacting particles, the fewer successful
collisions
How?
Add more reactant to the
same volume of solution
35. 4.4 Pressure
Why?
Pressure is used to describe particles in gases
The lower the pressure, the fewer successful
collisions
How?
Decrease the volume or
Increase the temperature
36. 4.5 Catalysts
Why?
Expensive to increase temperature or pressure
Do not get used up in reaction and can be
reused
How?
Catalysts are made from transition metals, e.g.
iron, nickel, platinum
Provide surface area for reacting particles to
come together and lower activation energy
37. 5.1 Energy changes
Exothermic reaction, Endothermic reaction,
e.g. respiration e.g. photosynthesis
• Energy ‘exits’ • Energy ‘enters’
reaction – heats reaction – cools
surroundings surroundings
• Thermometer • Thermometer
readings rises readings fall
38. 5.2 Energy and reversible
reactions
Exothermic reaction
Hydrated Anhydrous
copper sulphate copper sulphate + water
Endothermic reaction
40. 5.3 Haber process (again!)
Smaller vol. of pressure, pressure,
gas produced products products
N2 + 3H2 2NH3
Larger vol. of pressure, pressure,
gas produced products products
41. 5.3 Haber process (again!)
Temperature:
- Forward reaction is exothermic, so low temperature is preferred
- But this makes reaction slow
- Compromise by using 450OC
N2 + 3H2 2NH3
Catalyst:
Pressure: - Iron
- The higher the better - Speeds up both
- High pressure is dangerous! sides of reaction
- Compromise by using 200-350 atm
42. 6.1 Electrolysis
Electrolysis: splitting
up using electricity
Ionic substance
- molten (l)
- dissolved (aq)
Non-metal ion
Metal ion
43. 6.2 Changes at the electrodes
Solutions
Water contains the ions:
H+ and O2-
The less reactive element will
be given off at electrode
Oxidation is loss Reduction is gain
OIL RIG
Molten (PbBr) 2Br- Br2 + 2e- Pb2+ + 2e- Pb
Solution (KBr) 2Br- Br2 + 2e- 2H+ + 2e- H2
44. 6.3 Electrolysing brine
At anode 2Cl- (aq) Cl2 (g) + 2e-
At cathode 2H+ (aq) + 2e- H2 (g)
In solution Na+ and OH-
45. 6.4 Purifying copper
At anode 2H2O (l) 4H+ (aq) + O2 (g) + 2e-
At cathode Cu2+ (aq) + 2e- Cu (s)