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Topic: Lab: Galvanic Cells - How to calculate standard cell potential  (Read 20353 times)

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Offline sallyhansen

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #30 on: May 09, 2013, 04:19:56 PM »
So the above is the theoretical potential and the measured potential would be the voltmeter reading I have from the lab? Which I got 1.05V.

Offline Borek

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #31 on: May 09, 2013, 04:33:45 PM »
So the above is the theoretical potential and the measured potential would be the voltmeter reading I have from the lab? Which I got 1.05V.

Yes. And you are expected to compare 1.05V (experimental) with 1.1V (theoretical).
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Offline sallyhansen

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #32 on: May 09, 2013, 04:54:21 PM »
So the above is the theoretical potential and the measured potential would be the voltmeter reading I have from the lab? Which I got 1.05V.

Yes. And you are expected to compare 1.05V (experimental) with 1.1V (theoretical).
Which I did with this equation, which hopefully is formatted correctly

% diff. = value 1-value 2(*100)
            value 1+value 2
          = 1.1 – 1.05    (*100)
              1.1+1.05
          = 0.05
             2.15
          =2.33%

Offline Borek

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #33 on: May 09, 2013, 05:07:17 PM »
No, that's not what you did. What is 2.15?

[tex]difference~\% = \frac{theoretical - experimental}{theoretical}\times 100~\%[/tex]
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Offline sallyhansen

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #34 on: May 09, 2013, 05:28:54 PM »
No, that's not what you did. What is 2.15?

[tex]difference~\% = \frac{theoretical - experimental}{theoretical}\times 100~\%[/tex]

the 2.15 was me adding 1.1 and 1.05, which now I know is incorrect. Thanks for the equation, really

Offline sallyhansen

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #35 on: May 09, 2013, 05:34:06 PM »
No, that's not what you did. What is 2.15?

[tex]difference~\% = \frac{theoretical - experimental}{theoretical}\times 100~\%[/tex]

Also I ended up getting this. So would I subtract 100 by 10 to get 95.24% as the percent difference?
 
= 1.1 – 1.05/ 1.05 X 100
= 4.76%

Offline Borek

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Re: Lab: Galvanic Cells - How to calculate standard cell potential
« Reply #36 on: May 09, 2013, 05:58:54 PM »
4.76% is OK.
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