7 - Oxidation, Reduction and Redox reactions. Flashcards
What is oxidation?
Addition of oxygen
Loss of electrons.
What is reduction?
Removal of oxygen
Gain of electrons.
What is a redox reaction?
When both oxidation and reduction occur simultaneously.
What is a spectator ion?
An ion that takes no place in a reaction.
What is a reducing agent?
Electron donor
Gets oxidised.
What is an oxidising agent?
Electron acceptor
Gets reduced.
What are oxidation states?
Numbers that show what has been oxidised and what has been reduced in a redox reaction.
What do oxidation states tell us in ionic compounds?
How many electrons have been lost or gained.
What do oxidation states tell us in molecules?
Indicates the distribution of electrons of between elements of different electronegativity.
How does electronegativity affect the oxidation state?
The more electronegative the element the more negative the oxidation state.
What is the oxidation state of uncombined elements?
0
What is the oxidation state of hydrogen? (and the exception)
+1
except metal hydrides (NaH)
What is the oxidation state of Group 1?
+1
What is the oxidation state of Group 2?
+2
What is the oxidation state of Aluminium?
+3
What is the oxidation state of oxygen?(and the exception)
-2
except peroxides (OF2)
What is the oxidation state of flourine?
-1
What is the oxidation state of chlorine?(and the exception)
-1
except with F/O
What is the sum of oxidation states in compounds?
0
As all compounds are electrically neutral.
What are the conditions for a balanced redox equation?
The number of atoms of each element on each side of the equation is the same.
The total charge on each side of the equation is the same.
What is disproportionation?
When atoms of the same element are both oxidised AND reduced.
