topic 3 - redox I

Question 1

What is a redox reaction?

Answer 1

In a redox reaction, one species is oxidised while the other is reduced, which happens because of the loss and gain of electrons between the reacting species

Question 2

What is oxidation?

Answer 2

Oxidation [O] is a loss of electrons; a gain of oxygen and loss of hydrogen.

Question 3

What happens to the oxidation number when oxidation has occured?

Answer 3

If the oxidation number increases, then oxidation has occurred. When metals form compounds, they generally donate electrons to form positive ions and their oxidation number increases (positive oxidation numbers)

Question 4

What is a reducing agent?

Answer 4

A reducing agent donates electrons and gets oxidised.

Question 5

What is reduction?

Answer 5

Reduction [H] is a gain of electrons; a loss of oxygen and a gain of hydrogen.

Question 6

What happens to the oxidation number when reduction has occured?

Answer 6

If the oxidation number decreases, then reduction has occurred. When non-metals form compounds, they generally gain electrons to form negative ions and their oxidation numbers decreases (negative oxidation numbers)

Question 7

What is an oxidising agent?

Answer 7

An oxidising agent accepts electrons and gets reduced.

Question 8

What is a disproportionation reaction?

Answer 8

A disproportionation reaction is when one species is simultaneously oxidised and reduced in the same reaction.