AQA A Level Chemistry Redox Reactions Quiz and Flashcards

What does an oxidising agent do in a redox reaction?

Why do half equations need to be balanced in a redox reaction?

Which step is used to balance hydrogen in a half equation?

What happens to the oxidation number of a reducing agent in a redox reaction?

How are half equations combined to determine the overall redox reaction?

Why does an oxidising agent gain electrons in a redox reaction?

Which of the following defines oxidation?

What is the oxidation state of hydrogen?

In a charged compound, the oxidation states of the elements add up to what?

What does the acronym OILRIG stand for in relation to redox reactions?

What is the oxidation state of oxygen?

Which group of elements have an oxidation state of +1?

Oxidation, Reduction, and Redox Reactions

Oxidation is the loss of electrons, while reduction is the gain of electrons.
Oxidation and reduction occur simultaneously in a reaction, making them redox reactions.
The acronym OILRIG helps remember that oxidation is loss and reduction is gain.

Oxidation Number

Oxidation number gives the oxidation state of an element or ionic substance.
Rules for allocating oxidation states:
- Oxidation state of an element is zero.
- Oxidation states in a neutral compound add up to zero.
- Oxidation states in a charged compound add up to the total charge.
- Hydrogen has an oxidation state of +1.
- Oxygen has an oxidation state of -2.
- All halogens have an oxidation state of -1.
- Group I metals have an oxidation state of +1.

Oxidising and Reducing Agents

An oxidising agent accepts electrons from the species being oxidised, gaining electrons and being reduced.
A reducing agent donates electrons to the species being reduced, losing electrons and being oxidised.

Half Equations

Half equations show separate oxidation and reduction reactions in a redox reaction.
Half equations must be balanced in terms of species and charges.
A useful method for writing half equations:
- Balance all species excluding oxygen and hydrogen.
- Balance oxygen using H2O.
- Balance hydrogen using H+ ions.
- Balance changes using e- (electrons).
Half equations can be combined to determine the overall redox reaction, ensuring the number of electrons is the same for both half equations.

This quiz provides detailed notes on oxidation, reduction, and redox reactions in AQA Chemistry A-level 3.1.7. It covers concepts such as the definitions of oxidation and reduction, electron transfer, and the occurrence of oxidation and reduction simultaneously in reactions.