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Complex electrolysis question

Posted: Wed Aug 02, 2023 8:12 pm
by bohojekek
The question in regard to the attached image below is:
Explain why the carbon electrode cannot be replaced with an iron electrode.

The answer states that iron is a STRONGER REDUCING AGENT than fluorine and would be preferentially oxidised.

Iron’s standard potential for oxidation is +0.44 V. Fluorine’s standard potential for oxidation is -2.89 V.

This is my thought process: the stronger the reducing agent, the more likely the substance is to oxidise. The more likely a substance is to oxidise, the lower its standard electrode potential. So how is iron the stronger reducing agent if fluorine’s standard reduction potential is lower? Am I not meant to flip the signs when determining what reduces and oxidises even for species I know are oxidising?

Re: Complex electrolysis question

Posted: Wed Aug 02, 2023 11:43 pm
by ChenBeier
It is opposit
Iron’s standard potential for oxidation is +0.44 V. Fluorine’s standard potential for oxidation is -2.89 V.
Fe => Fe2+ + 2e- -0,44 V
2 F- => F2 + 2 e- +2,85 V
Iron has the lower redox potential.

Also Carbon will be attacked by flourine. Beside F2 also CF4 will be developed.