Redox Reactions
Chemistry: IB Diploma Higher Level, topic 6.6.3
Redox Reactions
Redox reactions are important in many areas of life (e.g. breathalysers). These reactions involve the loss and gain of electrons.
OIL RIG
- OIL RIG is a good mnemonic for remembering the difference between oxidation and reduction:
- Oxidation Is Loss of electrons.
- Reduction Is Gain of electrons.
Oxidising agents
- An oxidising agent oxidises something else.
- It takes electrons from another compound.
- This means it gains electrons itself.
- So an oxidising agent is itself reduced.
Reducing agents
- A reducing agent reduces something else.
- It gives electrons to another compound.
- This means it loses electrons itself.
- So a reducing agent itself is oxidised.
Example
- A + B → A+ + B−
- Here, B is an oxidising agent.
- It takes an electron from A, meaning A is oxidised.
- B is itself reduced.
- A is a reducing agent.
- A gives an electron to B, so B is reduced.
- A is itself oxidised.
Test yourself on Redox Reactions
Which of these best describes an oxidising agent?
Which of the following does a reducing agent NOT do?