What are the half reactions for the following redox reactions?
1) N2(g)+3F2(g)->2NF3(g)
2) 2Fe2O3(s)+3S(s)->4Fe(s)+3SO2(g)
1) N2(g)+3F2(g)->2NF3(g)
2) 2Fe2O3(s)+3S(s)->4Fe(s)+3SO2(g)
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N2---->2N +6e oxidation
3F2 +6e-----> 6F-1 reduction
These are now balanced for the electrons gained and lost
4Fe+3 + 12e---->4Fe reduction
3S----> 3S+4 + 12e- oxidation
In order for a reaction to occur the number of electrons lost must be equal to the number of electrons gained.
3F2 +6e-----> 6F-1 reduction
These are now balanced for the electrons gained and lost
4Fe+3 + 12e---->4Fe reduction
3S----> 3S+4 + 12e- oxidation
In order for a reaction to occur the number of electrons lost must be equal to the number of electrons gained.
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Half equations/reactions are used to show how many electrons are lost/gained by the species.This enables you to say which species is oxidised and which is reduced.
1) You know that an F atom will gain 1 electron so the half reaction is F + e^- >F^-
You can see that the N atom loses 3 electrons so the half reaction is N > N^3+
2) Two Fe atoms combined with 3 O atoms. O atoms are in GpV1 so they accept 2 electrons each,6 in total so each Fe atom has donated 3e^- to the O's so they are Fe^3+. the half reaction for iron is
Fe^3+ + 3^- > Fe . The S atoms lose 2e^- half reaction is S > S2^- + 2e^-
1) You know that an F atom will gain 1 electron so the half reaction is F + e^- >F^-
You can see that the N atom loses 3 electrons so the half reaction is N > N^3+
2) Two Fe atoms combined with 3 O atoms. O atoms are in GpV1 so they accept 2 electrons each,6 in total so each Fe atom has donated 3e^- to the O's so they are Fe^3+. the half reaction for iron is
Fe^3+ + 3^- > Fe . The S atoms lose 2e^- half reaction is S > S2^- + 2e^-