Question

concentration affects the electrode potential, but how do i determine if the electrode potential becomes more negative or more positive...etc

Answer 1

i ask this question because of the above question

Answer 2

i know option 2 n 3 are wrong, but why is 1 corrrect?

Answer 3

sorry for the slanted picture @.@

Answer 4

do you know the relation between electrode potential and equilibrium constant?

Answer 5

no, its not taught to me =/ is there any equation involved? im not required to use an equation =(

Answer 6

\[E = E ^{0} - \frac{RT }{ nF } \ln (Q)\]
this is nernst equation

for equilibrium, E = 0 and Q becomes K(eq) equilibrium constant

and the relation becomes
\[E ^{0} = \frac{ RT }{ nF }\ln K _{eq}\]

try to write relation for equilibrium constant for the 1st reaction.


you are not computing the answer to this question by using this equation
what you are doing is, trying to get a relation between the two quantities and see, if what the question says is right or not

Answer 7

do you follow what i said?

Answer 8

i cant follow you.. sorry..

Answer 9

is there an intuition behind whether the electrode potential would change in a certain way?

Answer 10

anish, just to clarify, when they mean "electrode potential" for option 1, do they mean the reduction of ethanoic acid to ethanol?

Answer 11

yes, there is a relation.
NERNST EQUATION.

for an equilibrium reaction,
\[E ^{0} = \frac{ RT }{ nF } \ln Keq\]

Keq for the first reaction is

\[\frac{ [CH3COOH][H+] }{ [CH3CH2OH] }\]

this means as the conc. of ethanol increases, the equilibrium constant will dectrease, and consequently, the value of electrode potential will decrease.



yes they mean exactly what you said.

Answer 12

should i try to tell you a simple way?/

use this attachment

Answer 13

this is a straightforward way,
no equation involved

Answer 14

Ahhh haha yes thank you. So whenever a question refers to "electrode potential" they mean the reduction of the eqn?

Answer 15

yes.. by convention, reduction potential is said to be electrode potential

Answer 16

THX!! ok last one, is there a way to convert methanol into methane??

Answer 17

a reduction is what we would need to make this conversion happen.

i don't know if we have any reagent to make this conversion to happen, but i am quite confident, that using electricity, we could make this happen.

for using electricity, we can make non-spontaneous processes to happen

Answer 18

we might use LiAlH4 too

see if this link helps..
http://www.masterorganicchemistry.com/2011/08/08/oxidation-ladders/

Answer 19

ahh ok, thank you anish!

Answer 20

welcm. :)

Answer 21

At any electrode, if you:
- increase the concentration of the oxidising agent, the potential will increase
- decrease the concentration of the oxidising agent, the potential will decrease

- increase the concentration of the reducing agent, the potential will decrease
- decrease the concentration of the reducing agent, the potential will increase