H2 chem: electrolysis

Audi SG

Using relevant E^* values from the Data Booklet to suggest reasons for the following observation at the anode.

The electrolysis of either dilute/ concentrated NaF (aq) produces only oxygen gas at the anode.

Cant explain the concentrated NaF part. Why does it still produce O2 gas at anode?

UltimaOnline SG

Using relevant E^* values from the Data Booklet to suggest reasons for the following observation at the anode.

The electrolysis of either dilute/ concentrated NaF (aq) produces only oxygen gas at the anode.

Cant explain the concentrated NaF part. Why does it still produce O2 gas at anode?

Because the oxidation potential of fluoride to fluorine is too negative (or put in another way, the reduction potential of fluorine to fluoride is too positive). Hence, it is more feasible for water or hydroxide ions to be oxidized at the anode instead of fluoride ions.

fluppocinonys SG

Hi I also have one question regarding Electrochemistry.

When copper is added to aqueous iron(III) chloride

The E cell value is calculated as 0.77 - 0.34 = +0.43

Why do we use 0.77 in this case? This means Fe3+ is reduced to Fe2+ only?

Why we don't consider the possibility of Fe3+ reduce to Fe and hence a value of -0.04?

Thanks!