Oxidisation And Reduction Flashcards
What is oxidation?
- The addition of oxygen.
- There is a loss of electrons.
- There is an increase in oxidation number.
What is reduction?
- The loss of oxygen.
- The gaining of electrons.
- A decrease in oxidation number.
What is an oxidising agent? Explain how this works.
A oxidising agent is a substance that causes oxidation. The oxidation agent takes the electrons and is therefore reduced in the process (since it gains electrons).
What is a reducing agent?
A reducing agent is a substance that causes reduction. The reducing agent supplies the electrons and is therefore oxidised in the process (since it loses electrons).
What is an oxidation number?
An oxidation number is the charge in which an atom of an element has, or appears to have, in a compound.
In the equation, Zn + Cu2+ —> Zn2+ + Cu, which of the products are the reducing and oxidising agent.
- Zn2+ is the reduction agent .
- Cu is the oxidising agent.
What’s the oxidation number of any un-combined element?
0
What’s the oxidation number for an ion with a charge?
The oxidation number is the same as the charge of the ion.
What is the oxidation number for a compound?
It must equal to 0.
What’s the oxidation number for oxygen?
-2 but there are two exceptions:
- H2O2 —> -1
- OF2 —> 2
What is the oxidation number for halogens?
-1, unless they’re bonded with a more electronegative element.
What’s the oxidation number for a complex ion?
The same as its charge.
How do you balance redox equations?
- Assign oxidation numbers to all atoms.
- Identify the atoms being oxidised and reduced.
- Get the difference in oxidation number between the oxidised and reduced atoms.
- The two differences will act as a ratio.
- Swap and apply the ratio to the equation.
- Check that each side is balanced.
Give an example of an oxidising agent.
Potassium permanganate
