6th edition, 14.35

Moderators: Chem_Mod, Chem_Admin

Hai-Lin Yeh 1J
Posts: 89
Joined: Fri Sep 28, 2018 12:16 am
Been upvoted: 1 time

6th edition, 14.35

Postby Hai-Lin Yeh 1J » Thu Mar 07, 2019 12:12 am

Determine the equilibrium constants for the following reactions:
(a) Mn(s) + Ti2+ (aq) <-> Mn2+(aq) + Ti(s)

In the solutions manual, how did they obtain the equation:
at 25C lnK = nE/0.02568 V. Also, is there a way to just plug in numbers into the original formula, lnK = nFE/RT? I'm having trouble because R has units K and F and T have units C. Also, can we just use log K = nE/0.0592, which is the one I have from my notes.

Posts: 56
Joined: Fri Sep 28, 2018 12:25 am

Re: 6th edition, 14.35

Postby julia_lok_2K » Thu Mar 07, 2019 12:27 am

The equation from the solutions manual is a simplified version of the original formula, the 0.02568 is what you get when you combine all the constants in the original formula.

You can directly plug the numbers into the original formula. I'm a bit confused by exactly what units you're referring to, but if I read it correctly constant R has units J/(K*mol) and T has unit K so the K should cancel out (you can always convert celsius to kelvin). 1C = 1 J/V, which should help with the units.

I think you can also you the logK equation, it's essentially the same as the first equation it's just that you're using log instead of ln, which results in a different constant that is 0.0592.

Hope this helps!

Return to “Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)”

Who is online

Users browsing this forum: No registered users and 2 guests