1.6.2
Electrochemical Series
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The Electrochemical Series
Standard reduction potentials are listed in the electrochemical series.

The electrochemical series
- We list lots of half-equations with their standard reduction potentials in a table called the electrochemical series.
- The most negative potentials (the hardest reductions to do) are at the top.
- The standard hydrogen electrode potential is in the middle at 0 V.
- The easiest reductions are at the bottom.

Calculating cell potentials
- We can use standard reduction potentials to calculate the standard cell potential. This will allow us to predict the outcome of reactions.
- The process for calculating the standard cell potential is:
- Pick your two half equations.
- Decide which is happening as an oxidation and which is happening as a reduction.
- Subtract the standard reduction potential for the oxidation from the potential for the reduction.
- Eθcell = Eθreduced − Eθoxidised

E.g. Magnesium and bromine
- The standard reduction potential for Mg2+ + 2e- ⇌ Mg(s) is Eθ = −2.37 V.
- The standard reduction potential for Br2 + 2e- ⇌ 2Br-(aq) is Eθ = 1.07 V.
- The magnesium potential is more negative, so will go in the oxidation direction.
- The bromine potential is more positive, so the bromine will be reduced.

E.g. Magnesium and bromine cont.
- The equation for the reaction between magnesium and bromine is:
- Mg(s) + Br2(aq) → MgBr2(s)
- Eθcell = 1.07 V − (−2.37 V) = 3.44 V
- Mg(s) + Br2(aq) → MgBr2(s)
Drawing Cells and Predicting Reactions
There is a standard shorthand way of drawing electrochemical cells in chemistry.

Shorthand way of drawing cells
- There’s a standard shorthand way of writing electrochemical cells.
- The more negative potential goes on the left.
- The more positive potential goes on the right.
- The oxidised forms go in the centre.
- The different couples are split by a double vertical line that indicates a salt bridge.

Predicting cell reactions
- We can use standard cell potentials to predict whether or not a reaction is feasible.
- If the standard cell potential is positive, the reaction is feasible.
- If the standard cell potential is negative, the reaction is NOT feasible.
1Physical Chemistry
1.1Atoms, Molecules & Stoichiometry
1.2Atomic Structure
1.2.1Fundamental Particles1.2.2Isotopes & Mass Number1.2.3Electron Shells, Sub-Shells & Orbitals1.2.4Electron Configuration1.2.5Ionisation Energy1.2.6Factors Affecting Ionisation Energies1.2.7Trends of Ionisation1.2.8Specific Impacts on Ionisation Energies1.2.9Electron Affinity1.2.10End of Topic Test - Atomic Structure1.2.11A-A* (AO2/3) - Atomic Structure
1.3Chemical Bonding
1.3.1Ionic Bonding1.3.2Covalent & Dative Bonding1.3.3Shapes of Molecules1.3.4Intermolecular Forces1.3.5Intermolecular Forces 21.3.6Electronegativity1.3.7Bond Length, Bond Energy, & Bond Polarity1.3.8Metallic Bonding1.3.9Physical Properties1.3.10End of Topic Test - Bonding1.3.11A-A* (AO2/3) - Bonding
1.4States of Matter
1.5Chemical Energetics
1.6Electrochemistry
1.7Equilibria
1.7.1Dynamic Equilibrium & Le Chatelier1.7.2Kc1.7.3Kp1.7.4pH1.7.5The Ionic Product of Water1.7.6Weak Acids & Bases1.7.7Introduction to Solubility Equilibria1.7.8Solubility Equilibria Calculations1.7.9Free Energy of Dissolution1.7.10pH and Solubility1.7.11Common-Ion Effect1.7.12End of Topic Test - Kp & Electrochemistry1.7.13A-A* (AO2/3) - Electrochemical Cells
1.8Partition Coefficient
1.9Reaction Kinetics
1.9.1Collision Theory1.9.2Orders, Rate Constants & Equations1.9.3Rate Graphs1.9.4Rate Determining Step1.9.5Maxwell-Boltzmann Distribution1.9.6Catalysts1.9.7Homogeneous Catalysts1.9.8Heterogeneous Catalysts1.9.9End of Topic Test - Kinetics1.9.10End of Topic Test - Rate Equations1.9.11A-A* (AO2/3) - Rate Equations
2Inorganic Chemistry
2.1The Periodic Table
2.2Group 2
2.3Group 17
2.4Transition Metals
3Organic Chemistry & Analysis
3.1Introduction to Organic Chemistry
3.2Hydrocarbons
3.2.1Fractional Distillation3.2.2Cracking3.2.3Combustion3.2.4Chlorination3.2.5End of Topic Test - Alkanes3.2.6Introduction to Alkenes3.2.7Reactions of Alkenes3.2.8Polymerisation Reactions3.2.9End of Topic Test - Alkenes3.2.10Arenes3.2.11Evidence for Structure of Arenes3.2.12Reactions of Benzene3.2.13End of Topic Test -Arenes
3.3Halogen Derivatives
3.4Hydroxy Compounds
3.5Carbonyl Compounds
3.6Carboxylic Acids & Derivatives
3.7Nitrogen Compounds
3.8Polymerisation
3.9Analytical Techniques
3.9.1Chromatography3.9.2High-Performance Liquid Chromatography3.9.3Gas Chromatography3.9.4IR Spectroscopy3.9.5Uses of IR Spectroscopy3.9.6Mass Spectrometry3.9.7Mass Spectrometry Analysis3.9.8Nuclear Magnetic Resonance3.9.9Carbon-13 NMR3.9.10Proton NMR I3.9.11Proton NMR II3.9.12End of Topic Test - Analytical Techniques3.9.13A-A* (AO2/3) - Analytical Techniques
Jump to other topics
1Physical Chemistry
1.1Atoms, Molecules & Stoichiometry
1.2Atomic Structure
1.2.1Fundamental Particles1.2.2Isotopes & Mass Number1.2.3Electron Shells, Sub-Shells & Orbitals1.2.4Electron Configuration1.2.5Ionisation Energy1.2.6Factors Affecting Ionisation Energies1.2.7Trends of Ionisation1.2.8Specific Impacts on Ionisation Energies1.2.9Electron Affinity1.2.10End of Topic Test - Atomic Structure1.2.11A-A* (AO2/3) - Atomic Structure
1.3Chemical Bonding
1.3.1Ionic Bonding1.3.2Covalent & Dative Bonding1.3.3Shapes of Molecules1.3.4Intermolecular Forces1.3.5Intermolecular Forces 21.3.6Electronegativity1.3.7Bond Length, Bond Energy, & Bond Polarity1.3.8Metallic Bonding1.3.9Physical Properties1.3.10End of Topic Test - Bonding1.3.11A-A* (AO2/3) - Bonding
1.4States of Matter
1.5Chemical Energetics
1.6Electrochemistry
1.7Equilibria
1.7.1Dynamic Equilibrium & Le Chatelier1.7.2Kc1.7.3Kp1.7.4pH1.7.5The Ionic Product of Water1.7.6Weak Acids & Bases1.7.7Introduction to Solubility Equilibria1.7.8Solubility Equilibria Calculations1.7.9Free Energy of Dissolution1.7.10pH and Solubility1.7.11Common-Ion Effect1.7.12End of Topic Test - Kp & Electrochemistry1.7.13A-A* (AO2/3) - Electrochemical Cells
1.8Partition Coefficient
1.9Reaction Kinetics
1.9.1Collision Theory1.9.2Orders, Rate Constants & Equations1.9.3Rate Graphs1.9.4Rate Determining Step1.9.5Maxwell-Boltzmann Distribution1.9.6Catalysts1.9.7Homogeneous Catalysts1.9.8Heterogeneous Catalysts1.9.9End of Topic Test - Kinetics1.9.10End of Topic Test - Rate Equations1.9.11A-A* (AO2/3) - Rate Equations
2Inorganic Chemistry
2.1The Periodic Table
2.2Group 2
2.3Group 17
2.4Transition Metals
3Organic Chemistry & Analysis
3.1Introduction to Organic Chemistry
3.2Hydrocarbons
3.2.1Fractional Distillation3.2.2Cracking3.2.3Combustion3.2.4Chlorination3.2.5End of Topic Test - Alkanes3.2.6Introduction to Alkenes3.2.7Reactions of Alkenes3.2.8Polymerisation Reactions3.2.9End of Topic Test - Alkenes3.2.10Arenes3.2.11Evidence for Structure of Arenes3.2.12Reactions of Benzene3.2.13End of Topic Test -Arenes
3.3Halogen Derivatives
3.4Hydroxy Compounds
3.5Carbonyl Compounds
3.6Carboxylic Acids & Derivatives
3.7Nitrogen Compounds
3.8Polymerisation
3.9Analytical Techniques
3.9.1Chromatography3.9.2High-Performance Liquid Chromatography3.9.3Gas Chromatography3.9.4IR Spectroscopy3.9.5Uses of IR Spectroscopy3.9.6Mass Spectrometry3.9.7Mass Spectrometry Analysis3.9.8Nuclear Magnetic Resonance3.9.9Carbon-13 NMR3.9.10Proton NMR I3.9.11Proton NMR II3.9.12End of Topic Test - Analytical Techniques3.9.13A-A* (AO2/3) - Analytical Techniques
Practice questions on Electrochemical Series
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