How do we represent the formation of #FeS# by the redox reaction of iron and sulfur?

1 Answer
anor277
Mar 6, 2017

#"Oxidation is the formal loss of electrons........"#

Explanation:

And thus, when zerovalent, i.e. elemental, iron is oxidized, we represent the oxidation on these terms:

#Fe rarr Fe^(2+) + 2e^-# #(i)#

On the other hand, #"reduction is the formal gain of electrons"#. For sulfur we have:

#S +2e^(-) rarr S^(2-)# #(ii)#

We conceive that iron and sulfur undergo formal electron transfer, so we add reactions #(i)+(ii)# so that electrons do not appear in the final equation:

#Fe + S rarr FeS#

And thus in the reverse reaction, #Fe^(2+)# is REDUCED to give elemental iron.

We would cross multiply the redox equations if there were different numbers of electrons involved in the individual redox reactions.

If iron were oxidized to #Fe^(3+)#, how would you represent the redox reaction?

Related questions
See all questions in Stoichiometry
Impact of this question
4397 views around the world
You can reuse this answer
Creative Commons License