Redox Flashcards
What happens in oxidation and reduction?
Electrons are transferred.
OIL RIG
Oxidation is Loss
Reduction is Gain
This is the other way around in terms of oxygen being gained and lost.
When does hydrogen NOT have an oxidation state of +1
When in metal hydrides like NaH (metal with a hydrogen)
When does oxygen NOT have an oxidation state of -2?
When in peroxides (-1) and in F20 (+2)
How to identify redox reactions?
By making half equations of the gaining and loss of electrons for each element in the reaction.`
Ca + 1/202 = CaO
Ca – Ca2+ + 2e-
1/2 O2 + 2e- = 02-
What is a reducing agent?
A reactant in a redox reaction that loses elcectrons and is oxidised.
What is an oxidising agent?
A reactant in a redox reaction that gains electrons and reduced.
What is the oxidation state of uncombined elements? (Cl2, O2, Fe)
0
What is the oxidation sate of ions?
= ion charge
eg: Ca2+ oxidation state is +2
Cl- is -1
What is the oxidation state of group 1 elements?
+1
What is the oxidation state of group 2 elements?
+2
What is the oxidation state of aluminium?
+3
When does chlorine NOT have an oxidation state of -1?
When bonded with F or 0. It is +1 because they are more electronegative.
What is the oxidation state of Flourine?
-1
What do you need to consider when finding the oxidation states of ions?
That the oxidation states od each element add to the overall ion charge
How do you identify whether something is an oxidation or reduction reaction?
Reduction is a decrease in oxidation number.
Oxidation is an increase in oxidation number.
