effect of temperature on electrode potentials

Watch this thread
The__Bait
Badges: 0
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 14 years ago
#1
i am struggling to understand how increasing the temperature increases electrode potentials. is this something to do with particle kinematics or le chatelier's principle?
0
reply
charco
Badges: 18
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 14 years ago
#2
Increasing the temperature AFFECTS electrode potentials, not increases them.

The electrode potential is a measure of the extent of a redox process - negative and the equilibrium lies relatively to the LHS (compared to the standard hydrogen electrode)

example: Zn2+(aq) + 2e --> Zn(s)

The process is not quite as simple as it appears. To move from right to left the equilibrium has to have the zinc atomised and then ionised and then the ions solvated.

Each of these processes is either exo or endothermic and is affected by the temperature.

The equilibrium between the ions and the pure metal is also affected by the temperature.

If the equilibrium is exothermic overall from left to right then an increase in the temperature will make the equilibrium move more to the left hand side making the electrode potential more negative.

The reverse is also true - if the equilibrium is endothermic overall from left to right then increasing the temperature makes the electrode potential more positive.
1
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Y13's - If you haven't confirmed your firm and insurance choices yet, why is that?

I am waiting until the deadline in case anything in my life changes (4)
26.67%
I am waiting until the deadline in case something else changes (e.g. exams/pandemic related concerns) (1)
6.67%
I am waiting until I can see the unis in person (2)
13.33%
I still have more questions before I make my decision (1)
6.67%
No reason, just haven't entered it yet (3)
20%
Something else (let us know in the thread!) (4)
26.67%

Watched Threads

View All