Organic molecules
The Gorgon gas project off the coast of north-west Australia is a joint project between the Chevron, ExxonMobil and Shell companies. It is estimated that it will provide liquefied natural gas, or LNG, for up to 40 years and will contribute billions of dollars to the Australian economy. LNG contains organic molecules, predominantly methane (CH4), and the gas produced will be used as a fuel to meet the energy needs of countries in our regions. This illustrates one extreme of the realm of organic chemistry – the large-scale use of hydrocarbon fuels which will be involved in combustion reactions.
At the other end of the scale are the reactions of more specialised organic molecules, produced to perform specific tasks that rely on certain types of reactions. These might play a role in situations such as the breakdown of food or the action of a pharmaceutical drug in our bodies. These areas of organic chemistry involve the production and analysis of specific molecules, and a thorough knowledge of the differences in the structure of the molecules involved is required.
Organic chemistry is the study of the properties, reactions and structure of compounds involving carbon. In this topic you will increase your knowledge of organic chemistry by investigating the structures and reactions of numerous types of organic molecules, ranging from alcohols to amino acids.
The topic should take approximately 10 hours.
Unit content
You will learn about:
- hydrocarbons
- names and structures of hydrocarbons
- reactions of hydrocarbons
- substitution reactions
- addition reactions
- functional groups in organic molecules
- alcohols
- structure of alcohols
- physical properties of alcohols
- reactions of alcohols
- oxidation reactions
- carboxylic acids
- alcohols, carboxylic acids and esters
- identification of alcohols
- nitrogen-containing compounds
- amines
- amino acids
- determination of formulae and structure
- empirical formulae
- molecular formulae and structure
- identification of an organic compound.
Read ideas for taking control of your learning here
The first part of the topic involves revision of material from Stage 2 Chemistry. It is important for you to do this thoroughly, especially the areas of naming compounds, structures and isomers. These are concepts that you will be using throughout the topic.
Strategies such as flow charts and comparison tables will help you to consolidate your learning and make links between the different ideas you will encounter. You will be shown some examples of how to use these, but it is important for you to design and use your own.
Molecular models will be useful in this topic, as they will help you to visualise both the structures and reactions of the organic molecules.
Towards the end of the topic you will be using half-equations to write equations for redox reactions. You should revise this area, and your calculation skills will also be tested when you have to calculate the empirical formulae of a range of organic compounds.
Read the unit outcomes here
By the end of this topic you should be able to:
- draw and name isomers
of alkanes and alkenes - write equations for combustion reactions, substitution reactions of alkanes and addition reactions of alkenes
- recognise the functional groups present in alcohols, aldehydes, ketones, carboxylic acids and esters
- explain how the chemical behaviour of a compound is dependent on the functional group in the molecule
- name simple examples of molecules containing functional groups
- draw structural formulae for primary, secondary and tertiary alcohols
- explain melting points, boiling points and solubility of alcohols in terms of the intermolecular interactions
- describe and write equations for oxidation reactions of alcohols
- use observations of reactions of alcohols to classify alcohols
- name and draw simple structural formulae for primary amines
- recognise the general structural formula for alpha (α) amino acids
- calculate the empirical and molecular formulae and determine the structure of organic compounds from analysis data.
