Electron Transfer in Fe + HCl Reaction: How Many Electrons are Involved?

AI Thread Summary
The discussion centers on determining the number of electrons transferred in the reaction between iron (Fe) and hydrochloric acid (HCl). Participants suggest breaking the reaction into half-reactions for oxidation and reduction to clarify the electron transfer process. It is noted that Fe is oxidized to Fe2+ while Cl is reduced, leading to a total transfer of two electrons. A crucial point is that one half-reaction must be reversed to align with the initial reactants. The final conclusion emphasizes writing the net ionic reaction to clearly identify the species being reduced.
mate1000
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Hey iv been given a tutorial question that says:
How many electrons are transferred in the following reaction?

Fe + 2HCl -> FeCl2 + H2

Now when you go to a redution potential table and get
Fe2+ + 2e- -> Fe(s)
2H+ + 2e- -> H2
Cl2 + 2e- -> 2Cl-

Do you have to do the reaction between the H and Cl first and then do the whole reaction or what?
Cheers
 
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Forget about table, try to split the reaction into two half reactions - reduction and oxidation.
 
If you look at the half reactions though don't both reactions have the electrons on the right hand side in order to get the right final equation, or am i missing something crucial out.
But if Fe is oxidation Fe-Fe2+ + 2e- and Cl is reduction Cl2 + 2e- - 2Cl-, then u would have a transfer of two electrons, right?
 
mate1000 said:
If you look at the half reactions though don't both reactions have the electrons on the right hand side in order to get the right final equation, or am i missing something crucial out.

What you are missing is fact, that you don't start wirh Fe2+ - so you have to reverse one of the reactions.

But if Fe is oxidation Fe-Fe2+ + 2e- and Cl is reduction Cl2 + 2e- - 2Cl-, then u would have a transfer of two electrons, right?

Fe is oxidized, that's OK.

Write net ionic reaction, you will see what is being reduced.
 
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