Is the positive terminal of a battery positively charged?

Click For Summary
The positive terminal of a battery, such as the Copper electrode in a Daniel cell, does not retain a net positive charge when the circuit is open, as modern batteries do not hold charges in their electrodes without a conducting path. In electrochemical cells, the electrodes exhibit equal and opposite charges when connected, but this charge becomes negligible when disconnected due to the small capacitance between them. The concept of electrodes acting as capacitors is acknowledged, with the charge value being a function of voltage and capacitance. The discussion raises questions about whether these principles apply universally to all galvanic cells. Overall, the behavior of battery electrodes in open circuits remains a complex topic in electrochemistry.
p.tryon
Messages
51
Reaction score
0
Does the positive electrode of a Daniel cell (the Copper electrode) actually have a net positive charge when the electrodes are not connected by a conducting material such as a wire? If not, does it have a net charge at all and how does this charge compare to the negative terminal?

Finally, are the answers to these questions true for every type of (galvanic) electrochemical cell??
 
Physics news on Phys.org
p.tryon said:
Does the positive electrode of a Daniel cell (the Copper electrode) actually have a net positive charge when the electrodes are not connected by a conducting material such as a wire? If not, does it have a net charge at all and how does this charge compare to the negative terminal?

Finally, are the answers to these questions true for every type of (galvanic) electrochemical cell??

Any cell that I can think of functions by moving electrons from an anode to a cathode. Since it is separating a charge, the electrodes have equal and opposite charges.

But when the circuit is open? I know that modern batteries don't retain the charges in their electrodes once the circuit is broken, but the Daniel Cell? I'm not sure... Is there a chemist in the building?
 
Battery's electrodes are charged. The value of the charge is \pm Q, where Q = CV, V is battery's voltage and C is the capacitance between the electrodes. Since the capacitance C is very small, the charge Q is usually negligible.
 
meopemuk said:
Battery's electrodes are charged. The value of the charge is \pm Q, where Q = CV, V is battery's voltage and C is the capacitance between the electrodes. Since the capacitance C is very small, the charge Q is usually negligible.

That's right! I never thought of the electrodes as capacitors, but I guess they are! So, does a 9V battery have more capacitance because of the way it is shaped? (the electrodes are closer together)

I would think so.
 
Archosaur said:
But when the circuit is open? I know that modern batteries don't retain the charges in their electrodes once the circuit is broken, but the Daniel Cell? I'm not sure... Is there a chemist in the building?

I've been interested in this question recently, and I was wondering if you could expand on this comment in this thread: https://www.physicsforums.com/showthread.php?t=363541"
 
Last edited by a moderator:

Similar threads

  • · Replies 58 ·
2
Replies
58
Views
5K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 36 ·
2
Replies
36
Views
6K
  • · Replies 14 ·
Replies
14
Views
5K
  • · Replies 16 ·
Replies
16
Views
3K
Replies
5
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K