August 23, 2019, 02:02:32 PM
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Topic: Confused with electrode potentials...  (Read 476 times)

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Offline shohaib712

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Confused with electrode potentials...
« on: February 11, 2019, 11:21:24 AM »
Does the voltmeter stop the current from passing through the wires, therefore preventing the flow of electrons between the 2 half cells?

Offline mjc123

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Re: Confused with electrode potentials...
« Reply #1 on: February 11, 2019, 11:31:14 AM »
Depends where you put the voltmeter. Want to draw us a circuit?

Offline shohaib712

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Re: Confused with electrode potentials...
« Reply #2 on: February 11, 2019, 11:54:40 AM »
This is what my textbook says:
(Ive highlighted the parts relevant to the question im asking)

https://drive.google.com/file/d/1TODTKjSPWrdxlkJIVb5prXiPIsfDjhtM/view?usp=drivesdk

Offline mjc123

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Re: Confused with electrode potentials...
« Reply #3 on: February 11, 2019, 12:09:09 PM »
I think the box tells you the answer, doesn't it?

Offline shohaib712

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Re: Confused with electrode potentials...
« Reply #4 on: February 11, 2019, 12:14:33 PM »
Yes but my other textbook says the exact opposite to it tho...

Online Borek

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Re: Confused with electrode potentials...
« Reply #5 on: February 11, 2019, 01:29:09 PM »
In general voltmeter should have as high internal resistance as possible. The higher, the better. Typically that will mean resistance in the range of MΩ(s), so (assuming typical electrochemical cell voltage in the 1 V range) you can expect currents in the μA range. Whether it is means "stopping" current from flowing or not is a matter of application, sometimes it is negligible, sometimes it is way too much.
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