Redox Reactions

Question 1

What is oxidation?

Answer 1

Oxidation is a loss of electrons

Question 2

What is reduction?

Answer 2

Reduction is a gain in electrons

Question 3

What is an oxidising agent?

Answer 3

An oxidising agent accepts electrons and gets reduced

Question 4

What is a reducing agent?

Answer 4

A reducing agent donates electrons and gets oxidised

Question 5

What is an oxidation state?

Answer 5

The oxidation state of an element tells you the total number of electrons it has donated or accepted

Question 6

Give 5 rules you can use to work out the oxidation state of an atom

Answer 6

1. Uncombined elements have an oxidation state of 0
2. Elements bonded to identical atoms have an oxidation state of 0
3. The oxidation state of a monatomic ion is the same as it’s charge
4. In compound ions, the oxidation state is the ion charge
5. The sum of the oxidation states for neutral compounds is 0

Question 7

Give the oxidation state rules for combined oxygen

Answer 7

Combined oxygen is nearly always -2, except:

In peroxides, where it’s -1
In flourides, where it’s +2
In O2F2, where it’s +1
In O2, where it’s 0

Question 8

Give the oxidation state rules for combined hydrogen

Answer 8

Combined hydrogen is nearly always +1, except:

In metal halides, where its -1
In H2, where it’s 0

Question 9

Roman numerals show what?

Answer 9

Oxidation states

Question 10

Ionic half equations show what?

Answer 10

ionic half equations show oxidation or reduction

Question 11

How do you make full equations for redox reactions?

Answer 11

You can combine half-equations for different oxidising and reducing agents together to make full equations for redox reactions