Chemistry Stack Exchange is a question and answer site for scientists, academics, teachers and students. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Often, a galvanic cell is illustrated as having two electrodes, two electrolytes, a salt bridge, and wires linking the electrodes to a voltmeter. However, isn’t a voltmeter connected in a circuit in parallel? This set up makes it seem as if it is being set up in series. How would it work, then?

I would much appreciate it if a circuit diagram (much like the ones you get in physics) could be included in the explanation.

share|improve this question
up vote 3 down vote accepted

Short answer, to the question title:

Yes, always.

Long answer:

Often, a galvanic cell is illustrated as having two electrodes, two electrolytes, a salt bridge, and wires bridging the electrodes to a voltmeter.

The piece missing from your list of components, in terms of a galvanic cell being put to practical use, is the load. You're correct, if a load were attached to the cell, it would be wired in parallel with the voltmeter.

A quick search turns up the following schematic along the lines of your description, from the UC Davis ChemWiki:

UC Davis galvanic cell schematic

From a brief scan, the construction of the half-cells and salt bridge look okay to me. I have not double-checked the half-cell potentials for accuracy.

If I read the schematic correctly, there is no load attached, and so the only thing completing the circuit with the galvanic cell is the voltmeter. In this case, the appropriate cell voltage would be read on the voltmeter. However, the current through the system would be negligibly small, due to the extremely high resistance of the voltmeter. The $\leftarrow e^-$ notation here indicates only the direction that current would flow through a lower-resistive load that were connected (again, yes, in parallel) with the voltmeter.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.