7.1 - 7.3 Oxidation, reduction and redox reactions Flashcards
1
Q
Define oxidation
A
- When the oxidation state of an element increases
- Gain of oxygen
- Loss of hydrogen
- Loss of electrons
2
Q
Define reduction
A
- When the oxidation state of an element decreases
- Loss of oxygen
- Gain of hydrogen
- Gain of electrons
3
Q
What is an oxidising agent?
A
Oxygen donor
Hydrogen and electron acceptor
4
Q
What is the significance of an oxidation state?
A
Shows the no. of electrons which it has lost or gained as a result of bonding
Positive no. = Oxidation
Negative no. = Reduction
5
Q
Oxidation state - Oxygen
A
-2 (except peroxides = -1, OF2 = +2)
6
Q
Oxidation state - Hydrogen
A
+1 (except metallic hydrides = -1)
7
Q
Oxidation state - Chlorine
A
-1 (except in compounds with F&O where it has positive values)
8
Q
Oxidation state - Fluorine
A
-1
9
Q
Oxidation state - Group 1
A
+1
10
Q
Oxidation state - Group 2
A
+2
11
Q
Oxidation state - Aluminium
A
+3
12
Q
Define catalyst
A
- A substance
- That speeds up a reaction
- And is chemically unchanged at the end
13
Q
Define oxidation state
A
Charge on the ion
