Source: https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-8-specific-impacts-on-ionisation-energies

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [International A Level](https://senecalearning.com/en-gb/revision-notes/international-a-level.md) › [Chemistry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry.md) › [Cambridge International](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international.md) › Specific Impacts on Ionisation Energies

# Specific Impacts on Ionisation Energies

Chemistry: Cambridge International A Level, topic 1.2.8

## Impact of Sub-Shell Structure on Ionisation Energy

The impact of the sub-shell structure is enough to sometimes outweigh and contrast general trends in ionisation energy.

### Example of sub-shell impact

![Example of sub-shell impact](https://image-v2.cdn.app.senecalearning.com/2018-08/e42dbd4f-4fc9-408f-a914-06ef666555dd/checked%201.2.1.1%20-%20period%203%20trend.png)

- An example of the impact of the sub-shell structure is the difference in ionisation energies between magnesium and aluminium within Period 3. 
 - They are in the same period and so we would expect aluminium's ionisation energy to be greater due to a greater nuclear charge.

### Contrast to the trend

![Contrast to the trend](https://image-v2.cdn.app.senecalearning.com/2018-08/e4a83ae1-2973-4b54-8cb9-eac06273a38a/odd-one-out-anomaly.png)

- But the ionisation energies are:
 - Mg = 738 kJ/mol.
 - Al = 578 kJ/mol.
- These values do not align with the general trend we predicted.
 - We need to look at the sub-shell structure of these atoms to understand what is going on.

### Mg vs Al sub-shell structure

![Mg vs Al sub-shell structure](https://image-v2.cdn.app.senecalearning.com/2018-08/58e21d43-296d-4f81-be16-3b94c84232b3/empty-shell-beach.jpg)

- Mg = 1s22s22p63s2
 - So the first ionisation removes an electron from the 3s orbital.
- Al = 1s22s22p63s23p1
 - So the first ionisation removes an electron from the 3p orbital.

### Sub-shell energies

![Sub-shell energies](https://image-v2.cdn.app.senecalearning.com/2018-08/f0dbef77-32ab-413f-a688-d6bb0360faf2/electrons-atom-.jpg)

- The 3p orbital is further from the nucleus on average than the 3s orbital.
 - So this orbital has a higher energy and its electrons have a lower electrostatic attraction to the positive nucleus.
 - It is also slightly shielded by the 3s2 electrons.
- So it's easier to ionise an electron in the 3p orbital than in the 3s orbital.
   - This explains why it is easier to ionise Al than Mg.
   - This effect outweighs the general trend we looked at first.

### Evidence

![Evidence](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/6.1.2%20-%20DNA/detective-1424831_640-min.jpg)

- From these arguments, we can use the relative first ionisation energy values of Mg and Al as evidence for sub-shell structures.

## Impact of Electron Repulsion on Ionisation Energy

The impact of electron repulsion can be seen in the ionisation energies of Group 5 and Group 6.

### Phosphorus and sulfur

![Phosphorus and sulfur](https://image-v2.cdn.app.senecalearning.com/2018-08/433207e7-ddb1-4885-8d60-b5be0db03d3d/electron%20repulsion%20phosphorus%20sulfur.png)

- Both P and S have their outer electron in a 3p orbital.
 - P = 1s22s22p63s23p3
 - S = 1s22s22p63s23p4
- The shielding for each atom's outer electron is identical.
 - S has a higher nuclear charge and so you might expect S to have a higher ionisation energy. This is NOT the case.

### Singly vs doubly occupied orbitals

![Singly vs doubly occupied orbitals](https://image-v2.cdn.app.senecalearning.com/2018-08/433207e7-ddb1-4885-8d60-b5be0db03d3d/electron%20repulsion%20phosphorus%20sulfur.png)

- The P electron is removed from a singly occupied orbital but the S electron is removed from a doubly occupied orbital.
 - S has a lower ionisation energy because electrons in the same orbital repel each other.
 - This means that an electron is easier to remove from a doubly occupied orbital.
- This gives more evidence for the electronic structure model we are using.

## Test yourself on Specific Impacts on Ionisation Energies

- How is ionisation energy expected to change as you go across Period 3?
- Which Period 3 element has the highest ionisation energy?
- Why is it easier to ionise a 3p electron than a 3s electron?
- Why is sulfur expected to have a higher ionisation energy than phosphorus?
- Which of the following is identical in phosphorus and sulfur?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/2eb3e96b-13a1-48db-b631-5d0098e3ed27/section/09846b3c-d36b-4b3c-ad1a-d6f3978f0c9e/session)

- Previous topic: [1.2.7 Trends of Ionisation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-7-trends-of-ionisation.md)
- Next topic: [1.2.9 Electron Affinity](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-9-electron-affinity.md)

## Chemistry: Cambridge International A Level contents

### 1 Physical Chemistry
- 1.1 Atoms, Molecules & Stoichiometry
  - [1.1.1 Relative Masses](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-1-relative-masses.md)
  - [1.1.2 The Mole](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-2-the-mole.md)
  - [1.1.3 Mass Spectrometry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-3-mass-spectrometry.md)
  - [1.1.4 Empirical & Molecular Formulae](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-4-empirical-and-molecular-formulae.md)
  - [1.1.5 Balanced Equations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-5-balanced-equations.md)
  - [1.1.6 Molar Volume](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-6-molar-volume.md)
  - [1.1.7 End of Topic Test - Amount of Substance](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-1-7-end-of-topic-test-amount-of-substance.md)
- 1.2 Atomic Structure
  - [1.2.1 Fundamental Particles](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-1-fundamental-particles.md)
  - [1.2.2 Isotopes & Mass Number](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-2-isotopes-and-mass-number.md)
  - [1.2.3 Electron Shells, Sub-Shells & Orbitals](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-3-electron-shells-sub-shells-and-orbitals.md)
  - [1.2.4 Electron Configuration](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-4-electron-configuration.md)
  - [1.2.5 Ionisation Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-5-ionisation-energy.md)
  - [1.2.6 Factors Affecting Ionisation Energies](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-6-factors-affecting-ionisation-energies.md)
  - [1.2.7 Trends of Ionisation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-7-trends-of-ionisation.md)
  - [1.2.8 Specific Impacts on Ionisation Energies](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-8-specific-impacts-on-ionisation-energies.md)
  - [1.2.9 Electron Affinity](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-9-electron-affinity.md)
  - [1.2.10 End of Topic Test - Atomic Structure](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-10-end-of-topic-test-atomic-structure.md)
  - [1.2.11 A-A* (AO2/3) - Atomic Structure](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-2-11-a-a-ao23-atomic-structure.md)
- 1.3 Chemical Bonding
  - [1.3.1 Ionic Bonding](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-1-ionic-bonding.md)
  - [1.3.2 Covalent & Dative Bonding](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-2-covalent-and-dative-bonding.md)
  - [1.3.3 Shapes of Molecules](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-3-shapes-of-molecules.md)
  - [1.3.4 Intermolecular Forces](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-4-intermolecular-forces.md)
  - [1.3.5 Intermolecular Forces 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-5-intermolecular-forces-2.md)
  - [1.3.6 Electronegativity](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-6-electronegativity.md)
  - [1.3.7 Bond Length, Bond Energy, & Bond Polarity](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-7-bond-length-bond-energy-and-bond-polarity.md)
  - [1.3.8 Metallic Bonding](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-8-metallic-bonding.md)
  - [1.3.9 Physical Properties](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-9-physical-properties.md)
  - [1.3.10 End of Topic Test - Bonding](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-10-end-of-topic-test-bonding.md)
  - [1.3.11 A-A* (AO2/3) - Bonding](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-3-11-a-a-ao23-bonding.md)
- 1.4 States of Matter
  - [1.4.1 Simple Covalent Molecules](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-1-simple-covalent-molecules.md)
  - [1.4.2 The Ideal Gas Equation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-2-the-ideal-gas-equation.md)
  - [1.4.3 States of Matter](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-3-states-of-matter.md)
  - [1.4.4 Particle Diagrams](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-4-particle-diagrams.md)
  - [1.4.5 The Liquid State](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-5-the-liquid-state.md)
  - [1.4.6 Giant Ionic Lattices](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-6-giant-ionic-lattices.md)
  - [1.4.7 Giant Metallic Lattices](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-7-giant-metallic-lattices.md)
  - [1.4.8 Giant Covalent Structures](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-8-giant-covalent-structures.md)
  - [1.4.9 Graphene & Fullerene](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-9-graphene-and-fullerene.md)
  - [1.4.10 Recycling](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-4-10-recycling.md)
- 1.5 Chemical Energetics
  - [1.5.1 Calorimetry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-1-calorimetry.md)
  - [1.5.2 Bond Enthalpies](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-2-bond-enthalpies.md)
  - [1.5.3 Enthalpy Changes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-3-enthalpy-changes.md)
  - [1.5.4 Hess' Law](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-4-hess-law.md)
  - [1.5.5 Born-Haber Cycles](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-5-born-haber-cycles.md)
  - [1.5.6 Born-Haber Cycle Calculations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-6-born-haber-cycle-calculations.md)
  - [1.5.7 Entropy](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-7-entropy.md)
  - [1.5.8 Free Energy](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-8-free-energy.md)
  - [1.5.9 End of Topic Test - Energetics](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-5-9-end-of-topic-test-energetics.md)
- 1.6 Electrochemistry
  - [1.6.1 Electrochemical Cells](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-6-1-electrochemical-cells.md)
  - [1.6.2 Electrochemical Series](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-6-2-electrochemical-series.md)
  - [1.6.3 Commercial Application](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-6-3-commercial-application.md)
  - [1.6.4 Nernst Equation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-6-4-nernst-equation.md)
  - [1.6.5 Redox](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-6-5-redox.md)
- 1.7 Equilibria
  - [1.7.1 Dynamic Equilibrium & Le Chatelier](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-1-dynamic-equilibrium-and-le-chatelier.md)
  - [1.7.2 Kc](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-2-kc.md)
  - [1.7.3 Kp](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-3-kp.md)
  - [1.7.4 pH](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-4-ph.md)
  - [1.7.5 The Ionic Product of Water](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-5-the-ionic-product-of-water.md)
  - [1.7.6 Weak Acids & Bases](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-6-weak-acids-and-bases.md)
  - [1.7.7 Introduction to Solubility Equilibria](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-7-introduction-to-solubility-equilibria.md)
  - [1.7.8 Solubility Equilibria Calculations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-8-solubility-equilibria-calculations.md)
  - [1.7.9 Free Energy of Dissolution](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-9-free-energy-of-dissolution.md)
  - [1.7.10 pH and Solubility](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-10-ph-and-solubility.md)
  - [1.7.11 Common-Ion Effect](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-11-common-ion-effect.md)
  - [1.7.12 End of Topic Test - Kp & Electrochemistry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-12-end-of-topic-test-kp-and-electrochemistry.md)
  - [1.7.13 A-A* (AO2/3) - Electrochemical Cells](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-7-13-a-a-ao23-electrochemical-cells.md)
- 1.8 Partition Coefficient
  - [1.8.1 Kpc](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-8-1-kpc.md)
- 1.9 Reaction Kinetics
  - [1.9.1 Collision Theory](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-1-collision-theory.md)
  - [1.9.2 Orders, Rate Constants & Equations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-2-orders-rate-constants-and-equations.md)
  - [1.9.3 Rate Graphs](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-3-rate-graphs.md)
  - [1.9.4 Rate Determining Step](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-4-rate-determining-step.md)
  - [1.9.5 Maxwell-Boltzmann Distribution](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-5-maxwell-boltzmann-distribution.md)
  - [1.9.6 Catalysts](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-6-catalysts.md)
  - [1.9.7 Homogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-7-homogeneous-catalysts.md)
  - [1.9.8 Heterogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-8-heterogeneous-catalysts.md)
  - [1.9.9 End of Topic Test - Kinetics](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-9-end-of-topic-test-kinetics.md)
  - [1.9.10 End of Topic Test - Rate Equations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-10-end-of-topic-test-rate-equations.md)
  - [1.9.11 A-A* (AO2/3) - Rate Equations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/1-9-11-a-a-ao23-rate-equations.md)

### 2 Inorganic Chemistry
- 2.1 The Periodic Table
  - [2.1.1 The Periodic Table](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-1-the-periodic-table.md)
  - [2.1.2 Trends in the Periodic Table](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-2-trends-in-the-periodic-table.md)
  - [2.1.3 End of Topic Test - Periodicity & Trends](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-3-end-of-topic-test-periodicity-and-trends.md)
  - [2.1.4 Ceramics](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-4-ceramics.md)
  - [2.1.5 Period 3 Elements & Oxides](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-5-period-3-elements-and-oxides.md)
  - [2.1.6 Period 3 Oxides](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-6-period-3-oxides.md)
  - [2.1.7 End of Topic Test - Period 3](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-1-7-end-of-topic-test-period-3.md)
- 2.2 Group 2
  - [2.2.1 Group 2 Chemistry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-2-1-group-2-chemistry.md)
- 2.3 Group 17
  - [2.3.1 Introduction to Halogens](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-3-1-introduction-to-halogens.md)
  - [2.3.2 Reactions of Halogens](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-3-2-reactions-of-halogens.md)
  - [2.3.3 Chlorine & Chlorate(I)](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-3-3-chlorine-and-chloratei.md)
  - [2.3.4 End of Topic Test - Group 17](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-3-4-end-of-topic-test-group-17.md)
  - [2.3.5 A-A* (AO2/3) - Periodicity, Group 2 & 17](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-3-5-a-a-ao23-periodicity-group-2-and-17.md)
- 2.4 Transition Metals
  - [2.4.1 General Properties](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-1-general-properties.md)
  - [2.4.2 Titrations](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-2-titrations.md)
  - [2.4.3 Shapes of Complex Ions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-3-shapes-of-complex-ions.md)
  - [2.4.4 Variable Oxidation States](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-4-variable-oxidation-states.md)
  - [2.4.5 Ligands](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-5-ligands.md)
  - [2.4.6 Colours of Ions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-6-colours-of-ions.md)
  - [2.4.7 Stereoisomerism of Complex Ions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-7-stereoisomerism-of-complex-ions.md)
  - [2.4.8 Cisplatin](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-8-cisplatin.md)
  - [2.4.9 Ligand Substitutions & Kstab](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-9-ligand-substitutions-and-kstab.md)
  - [2.4.10 End of Topic Test - Transition Metals](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-10-end-of-topic-test-transition-metals.md)
  - [2.4.11 A-A* (AO2/3) - Transition Metals](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-4-11-a-a-ao23-transition-metals.md)
- 2.5 Nitrogen & Sulfur
  - [2.5.1 Nitrogen & Ammonia](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-1-nitrogen-and-ammonia.md)
  - [2.5.2 Formulated vs Manure Fertilisers](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-2-formulated-vs-manure-fertilisers.md)
  - [2.5.3 Nitrogen Containing Fertilisers](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-3-nitrogen-containing-fertilisers.md)
  - [2.5.4 Fertilizers & Eutrophication](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-4-fertilizers-and-eutrophication.md)
  - [2.5.5 Common Atmospheric Pollutants & Their Properties](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-5-common-atmospheric-pollutants-and-their-properties.md)
  - [2.5.6 Catalytic Converters](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-6-catalytic-converters.md)
  - [2.5.7 Atmospheric Oxides](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/2-5-7-atmospheric-oxides.md)

### 3 Organic Chemistry & Analysis
- 3.1 Introduction to Organic Chemistry
  - [3.1.1 Naming Conventions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-1-1-naming-conventions.md)
  - [3.1.2 Mechanism](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-1-2-mechanism.md)
  - [3.1.3 Isomerism](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-1-3-isomerism.md)
  - [3.1.4 End of Topic Test - Introduction to Organic Chem](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-1-4-end-of-topic-test-introduction-to-organic-chem.md)
- 3.2 Hydrocarbons
  - [3.2.1 Fractional Distillation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-1-fractional-distillation.md)
  - [3.2.2 Cracking](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-2-cracking.md)
  - [3.2.3 Combustion](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-3-combustion.md)
  - [3.2.4 Chlorination](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-4-chlorination.md)
  - [3.2.5 End of Topic Test - Alkanes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-5-end-of-topic-test-alkanes.md)
  - [3.2.6 Introduction to Alkenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-6-introduction-to-alkenes.md)
  - [3.2.7 Reactions of Alkenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-7-reactions-of-alkenes.md)
  - [3.2.8 Polymerisation Reactions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-8-polymerisation-reactions.md)
  - [3.2.9 End of Topic Test - Alkenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-9-end-of-topic-test-alkenes.md)
  - [3.2.10 Arenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-10-arenes.md)
  - [3.2.11 Evidence for Structure of Arenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-11-evidence-for-structure-of-arenes.md)
  - [3.2.12 Reactions of Benzene](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-12-reactions-of-benzene.md)
  - [3.2.13 End of Topic Test -Arenes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-2-13-end-of-topic-test-arenes.md)
- 3.3 Halogen Derivatives
  - [3.3.1 Properties of Haloalkanes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-3-1-properties-of-haloalkanes.md)
  - [3.3.2 Substitution Reactions of Haloalkanes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-3-2-substitution-reactions-of-haloalkanes.md)
  - [3.3.3 Environmental Impacts of Haloalkanes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-3-3-environmental-impacts-of-haloalkanes.md)
  - [3.3.4 End of Topic Test - Halogenoalkanes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-3-4-end-of-topic-test-halogenoalkanes.md)
- 3.4 Hydroxy Compounds
  - [3.4.1 Types of Alcohol](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-1-types-of-alcohol.md)
  - [3.4.2 Oxidation 1](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-2-oxidation-1.md)
  - [3.4.3 Oxidation 2](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-3-oxidation-2.md)
  - [3.4.4 Elimination](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-4-elimination.md)
  - [3.4.5 Acids & Esters](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-5-acids-and-esters.md)
  - [3.4.6 Acyl Chlorides & Acylation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-6-acyl-chlorides-and-acylation.md)
  - [3.4.7 Phenols & Their Reactions](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-7-phenols-and-their-reactions.md)
  - [3.4.8 End of Topic Test - Alcohols](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-4-8-end-of-topic-test-alcohols.md)
- 3.5 Carbonyl Compounds
  - [3.5.1 Carbonyls](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-5-1-carbonyls.md)
  - [3.5.2 Hydrogen Bonding & Carbonyls](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-5-2-hydrogen-bonding-and-carbonyls.md)
  - [3.5.3 Aldehydes & Ketones](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-5-3-aldehydes-and-ketones.md)
  - [3.5.4 Tri-Iodomethane Reaction](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-5-4-tri-iodomethane-reaction.md)
  - [3.5.5 End of Topic Test -Carbonyls](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-5-5-end-of-topic-test-carbonyls.md)
- 3.6 Carboxylic Acids & Derivatives
  - [3.6.1 Properties of Carboxylic Acids](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-6-1-properties-of-carboxylic-acids.md)
  - [3.6.2 Esters](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-6-2-esters.md)
  - [3.6.3 Acyl Chlorides](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-6-3-acyl-chlorides.md)
  - [3.6.4 End of Topic Test - Carboxylic Acids](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-6-4-end-of-topic-test-carboxylic-acids.md)
- 3.7 Nitrogen Compounds
  - [3.7.1 Nature & Preparation of Amines](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-7-1-nature-and-preparation-of-amines.md)
  - [3.7.2 Basicity & Nucleophilicity](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-7-2-basicity-and-nucleophilicity.md)
  - [3.7.3 Amides](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-7-3-amides.md)
  - [3.7.4 Reactions of Amino Acids](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-7-4-reactions-of-amino-acids.md)
  - [3.7.5 Amino Acids](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-7-5-amino-acids.md)
- 3.8 Polymerisation
  - [3.8.1 Properties of Addition Polymers](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-1-properties-of-addition-polymers.md)
  - [3.8.2 Condensation Polymerisation](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-2-condensation-polymerisation.md)
  - [3.8.3 Effects of Side-Chains on Polymers](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-3-effects-of-side-chains-on-polymers.md)
  - [3.8.4 Hydrolysis of Ester & Amide Groups](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-4-hydrolysis-of-ester-and-amide-groups.md)
  - [3.8.5 Proteins](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-5-proteins.md)
  - [3.8.6 DNA](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-6-dna.md)
  - [3.8.7 Adhesive & Conducting Polymers](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-7-adhesive-and-conducting-polymers.md)
  - [3.8.8 End of Topic Test - Amines & Proteins](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-8-8-end-of-topic-test-amines-and-proteins.md)
- 3.9 Analytical Techniques
  - [3.9.1 Chromatography](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-1-chromatography.md)
  - [3.9.2 High-Performance Liquid Chromatography](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-2-high-performance-liquid-chromatography.md)
  - [3.9.3 Gas Chromatography](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-3-gas-chromatography.md)
  - [3.9.4 IR Spectroscopy](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-4-ir-spectroscopy.md)
  - [3.9.5 Uses of IR Spectroscopy](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-5-uses-of-ir-spectroscopy.md)
  - [3.9.6 Mass Spectrometry](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-6-mass-spectrometry.md)
  - [3.9.7 Mass Spectrometry Analysis](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-7-mass-spectrometry-analysis.md)
  - [3.9.8 Nuclear Magnetic Resonance](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-8-nuclear-magnetic-resonance.md)
  - [3.9.9 Carbon-13 NMR](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-9-carbon-13-nmr.md)
  - [3.9.10 Proton NMR I](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-10-proton-nmr-i.md)
  - [3.9.11 Proton NMR II](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-11-proton-nmr-ii.md)
  - [3.9.12 End of Topic Test - Analytical Techniques](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-12-end-of-topic-test-analytical-techniques.md)
  - [3.9.13 A-A* (AO2/3) - Analytical Techniques](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-9-13-a-a-ao23-analytical-techniques.md)
- 3.10 Organic Synthesis
  - [3.10.1 Chirality & Drug Synthesis](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-10-1-chirality-and-drug-synthesis.md)
  - [3.10.2 Organic Synthesis](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-10-2-organic-synthesis.md)
  - [3.10.3 Examples of Synthetic Routes](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-10-3-examples-of-synthetic-routes.md)
  - [3.10.4 End of Topic Test - Organic Synthesis](https://senecalearning.com/en-gb/revision-notes/international-a-level/chemistry/cambridge-international/3-10-4-end-of-topic-test-organic-synthesis.md)
