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Chemistry: essential concepts

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Chemistry is fundamental to our modern world, touching all aspects of our lives; food, health, materials, energy and our environment. Indeed, the solutions for many of the challenges facing the world will require Chemistry as a key facilitating science. This highly interactive module provides a broad foundation in organic, inorganic, and physical chemistry. It explores organic compounds and their synthesis, spectroscopic analysis, the Periodic Table and the reactivity of metals and non-metals, bonding and molecular shape, thermodynamics and kinetics. The practical nature of chemistry will be emphasised throughout. There will be an optional, laboratory-based residential school. The cost of accommodation, meals and travel for the optional residential school is not included in the module fee.

What you will study

The module is delivered entirely online. Audio, video and interactive activities are integrated throughout the module and you will need to download a free external software package.

Block 1: The periodic table
Block 1 focuses on a core concept of chemistry, the periodic table. Trends in properties of elements and their simple compounds are discussed and the predictive powers of the Periodic Table emphasised. Extraction of metals is related to their chemical reactivity and the chemistry of group 1 and 17 elements is given in more detail. In this block you will go on to consider Lewis structures and the prediction of molecular shape.

Block 2: Chemical bonding
Block 2 introduces atomic and molecular orbitals, as you take a pictorial approach to quantum mechanics rather than being purely mathematical.

Block 3: Organic molecules
Block 3 looks at the structure of organic molecules, their stereochemistry and includes an introduction to organic nomenclature. Videos and interactive diagrams are used to aid your appreciation of the three-dimensional nature of the molecules. The software package will enable you to produce chemical structures electronically.

Block 4: Chemical thermodynamics and equilibrium
Block 4 discusses enthalpy, entropy and Gibbs free energy. These thermodynamic quantities are used to examine the principles of metal extraction quantitatively. The use of Ellingham diagrams is explained in this context. The Gibbs free energy is related to equilibrium constants and redox potentials. Audio instructions are provided to guide you through example calculations and some diagrams. You will also be introduced to an online chemistry data book and observe an online experiment in thermochemistry.

Block 5: Chemical kinetics
Block 5 considers the role of the rate of reaction, and introduces chemical kinetics. A web-based program for plotting and analysing graphs is introduced and is used to obtain information from experimental data. As part of this block, there is a virtual kinetics experiment.

Block 6: An introduction to organic reaction mechanisms
Block 6 introduces the functional group concept of a group of atoms within an organic molecule that display particular chemical properties, and the common reaction mechanisms of organic substitution and elimination reactions are discussed. Videos are used to illustrate what happens during such reactions at the molecular level.

Block 7: Alkenes and aromatics
Block 7 continues the examination of organic reaction mechanisms started in Block 6, with a discussion of addition reactions. This is followed by a detailed look at aromatic substitution reactions.

Block 8: Materials chemistry
Block 8 explores the arrangements of atoms in different types of solid. The concepts of lattices and unit cells are introduced. Metal structures are discussed in terms of close-packing of spheres, and this is extended to show how simple ionic structures can be built up from close-packed structures. Building on Block 4, the use of Born-Haber cycles to obtain lattice energies is explored. Close-packing of spheres and the build-up of more complex structures is demonstrated in a series of videos.

Block 9: Molecular characterisation and spectroscopic analysis
Block 9 looks at methods for separating and purifying chemical compounds, and then discusses the spectroscopic techniques used to determine the nature and structure of a compound. The techniques include UV/visible spectroscopy, infrared and Raman spectroscopy, NMR and mass spectrometry. Extensive online exercises are used to teach the use of infrared and NMR spectroscopy to identify molecules.

Block 10: Introduction to first row transition elements
Block 10 introduces you to the chemistry of the transition elements. The role of d orbitals in determining the properties of these elements and their compounds is explored and a simple orbital theory, crystal field theory, which can account for a number of these properties, is introduced. Many of the reactions studied are illustrated by video sequences.

Block 11: Carbonyl and organometallic chemistry
Block 11 expands your knowledge of organic reactions by introducing the chemistry of carbonyl compounds and organometallic compounds. An important organometallic reaction is synthesis using a Grignard reaction and there is a video of an example of this.

Block 12: Organic synthesis
Block 12 pursues possible strategies for synthesising organic compounds, particularly those of interest to the pharmaceutical and related industries. You learn how to plan a set of reactions that will lead to a desired product; for example, the compound responsible for the scent of a flower. The importance of overall yield reaction and the cost of starting materials are emphasised. A video showing how the principles of retrosynthetic analysis can be applied to the production of Tamiflu® forms part of this block.

Block 13: Main-group chemistry
Block 13 returns to the chemistry of the main-group elements which was introduced in Block 1. Water in rivers, streams, ponds, lakes, the water from taps and even bottled water can contain a variety of inorganic species ranging from the beneficial to the toxic. This block explores the chemistry of these species and of some of the elements they contain. Finally ways of undertaking chemical reactions in a more environmentally friendly way are discussed.

Entry requirements

This is an OU Level 2 module: you need to have a good knowledge of the subject area through either Level 1 study with the OU or equivalent study at another university.

You must be familiar with the chemistry and mathematical content in the OU Level 1 modules Questions in science  (S111) and Science: concepts and practice  (S112).

Check you’re ready for Chemistry: essential concepts  (S215) with our self-assessed quiz.

If you’re still not sure you’re ready, talk to an adviser.

What's included

The module is delivered entirely online and all study material, with the exception of the chemical structure drawing package, is accessible via the module website which includes:

  • a week-by-week study planner
  • course-specific module materials
  • audio and video content
  • assignment details and submission section
  • online tutorial access.
  • on-screen experiments and remote access to laboratory instrumentation
  • extensive preparatory materials with module team support.

You will need

A scientific calculator.

Computing requirements

You’ll need broadband internet access and a desktop or laptop computer with an up-to-date version of Windows (10 or 11). Any macOS is unsuitable with this module.

Any additional software will be provided or is generally freely available.

To join in spoken conversations in tutorials, we recommend a wired headset (headphones/earphones with a built-in microphone).

Our module websites comply with web standards and any modern browser is suitable for most activities.

Our OU Study mobile app will operate on all current, supported versions of Android and iOS. It’s not available on Kindle.

It’s also possible to access some module materials on a mobile phone, tablet device or Chromebook. However, as you may be asked to install additional software or use certain applications, you’ll also require a desktop or laptop as described above.

Teaching and assessment

Support from your tutor

Throughout your module studies, you’ll get help and support from your assigned module tutor. They’ll help you by:

  • Marking your assignments (TMAs) and providing detailed feedback for you to improve.
  • Guiding you to additional learning resources.
  • Providing individual guidance, whether that’s for general study skills or specific module content.
  • Facilitating online discussions between your fellow students, in the dedicated module and tutor group forums.

Module tutors also run online tutorials throughout the module. Where possible, recordings of online tutorials will be made available to students. While these tutorials won’t be compulsory for you to complete the module, you’re strongly encouraged to take part.


The assessment details for this module can be found in the facts box.

Laboratory schools

The School of Life, Health and Chemical Sciences offers optional laboratory schools in Milton Keynes at an additional cost. Laboratory schools are not part of this module; however, they are compulsory if you’re studying towards one of the following chemistry qualifications:

If you’re not studying towards one of the above qualifications, the laboratory schools may be of interest if you wish to gain relevant hands-on laboratory experience.

Further information and instructions for booking are on the SS021 website.

If you have a disability

The OU strives to make all aspects of study accessible to everyone and this Accessibility Statement outlines what studying S215 involves. You should use this information to inform your study preparations and any discussions with us about how we can meet your needs.

Future availability

Chemistry: essential concepts (S215) starts once a year – in October.

This page describes the module that will start in October 2023.

We expect it to start for the last time in October 2023.

Course work includes:

6 Tutor-marked assignments (TMAs)
No residential school

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