Calculating the Voltage required for Cell (1 Viewer)

[wrxsti]

Hey.... i know that its E cathode - E Anode for a Galvanic Cell.....
But wats the formula for an Electrolytic Cell ?? We havent passed this part in school but i would like to know as it gets fustrating doing past papers and not being able to ONLY do this part.......
Thankssss

 

[xiao1985]

exactly the same.... with only 2 exceptions: 1) you will get a negative number (meaning it requires input of voltage) and 2) you need slightly higher voltage ( reason why has not been found yet, but apparently has something to do with entropy of gases etc).

 

[wrxsti]

thanks . but will it always be a negative number..... ? like if you have Silver (0.80V) and Fe3+ (0.77V)
then E cathode - Eanode
= 0.03 V which is positive

 

[6CanDyMaN9]

pretty sure that for Electrolytic Cells its E anode - E cathode... cause i don't think E cathode - E anode will eva give u a negative answer because the anode is the one that oxidises and the ones that oxidise have a lower voltage (usually negative) and a number - (lower number/negative number) = positive.

 

[xiao1985]

thanks . but will it always be a negative number..... ? like if you have Silver (0.80V) and Fe3+ (0.77V)
then E cathode - Eanode
= 0.03 V which is positive

that'd be a galvanic cell though