Redox l

Question 1

What is oxidation?

Answer 1

The loss of electrons

Question 2

What is reduction?

Answer 2

The gain of electrons

Question 3

What does the oxidation number of an atom tell you?

Answer 3

How many electrons it has lost or gained

Question 4

What are the rules of oxidation numbers?

Answer 4

1. Elements have an oxidation number of 0
2. Oxidation number of atoms in a neutral compound is 0
3. Oxidation number of ionic compounds add up to the overall charge

Question 5

What is the oxidation number of group 1 elements?

Answer 5

+1

Question 6

What is the oxidation number of group 2 elements?

Answer 6

+2

Question 7

What is the oxidation number of aluminium?

Answer 7

+3

Question 8

What is the oxidation number of hydrogen?

Answer 8

+1
except metal hydrides where it is -1

Question 9

What is the oxidation number of fluorine?

Answer 9

-1

Question 10

What is the oxidation number of group 7 elements?

Answer 10

Usually -1
Except in compounds with F and O, then it is positive e.g. O2-Cl2^+2

Question 11

What is the oxidation number of oxygen?

Answer 11

-2
Except peroxides where it is -1
Or in OF2 where it is +2

Question 12

Can elements have a range of oxidation states?

Answer 12

Yes
e.g. N can lose 5 electrons or gain 3 electrons

Question 13

How can we tell if oxidation has taken place in a reaction?

Answer 13

The oxidation number increases

Question 14

How can we tell of reduction has taken place in a reaction?

Answer 14

The oxidation number decreases

Question 15

What are spectator ions?

Answer 15

Ions in a reaction that have not undergone oxidation or reduction. They remain the same on both sides of the equation