Mistake in the exam! (1 Viewer)

nichorowitz

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Anyone else pick up the mistake?
In the galvanic cell where you had to calculate cell potential the electrolytes weren't 1.0 mol/L therefore the standard potential table had the wrong values and it was impossible to correctly calculate the cell potential.

;)
 

CalumGemmell

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Anyone else pick up the mistake?
In the galvanic cell where you had to calculate cell potential the electrolytes weren't 1.0 mol/L therefore the standard potential table had the wrong values and it was impossible to correctly calculate the cell potential.

;)
I don't think the concentration has anything to do with the values for the standard reduction potentials.
 

mirakon

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Anyone else pick up the mistake?
In the galvanic cell where you had to calculate cell potential the electrolytes weren't 1.0 mol/L therefore the standard potential table had the wrong values and it was impossible to correctly calculate the cell potential.

;)
i don't think this matters tbh
 

frankcat1

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Actually I think it does matter from what I've read
"The cell potential is a useful value when it can be compared to other cell potentials obtained under the same standard set of conditions—that is, when all participating gases exist at a pressure of 1 atm, and all ions are present in a concentration of 1 mol L-1" from - http://chemcases.com/cisplat/cisplat04.htm

"The values are for the following conditions: ...the effective concentration of 1 mol/L for each aqueous species" - http://en.wikipedia.org/wiki/Standard_electrode_potential_(data_page)
 

CalumGemmell

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Actually I think it does matter from what I've read
"The cell potential is a useful value when it can be compared to other cell potentials obtained under the same standard set of conditions—that is, when all participating gases exist at a pressure of 1 atm, and all ions are present in a concentration of 1 mol L-1" from - http://chemcases.com/cisplat/cisplat04.htm

"The values are for the following conditions: ...the effective concentration of 1 mol/L for each aqueous species" - http://en.wikipedia.org/wiki/Standard_electrode_potential_(data_page)
Same conditions, they had the same volume and concentration, so it may still be correct? Also, what was the volume and conc.'s of the electrolytes?
 

yum135

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Anyone else pick up the mistake?
In the galvanic cell where you had to calculate cell potential the electrolytes weren't 1.0 mol/L therefore the standard potential table had the wrong values and it was impossible to correctly calculate the cell potential.

;)

OMG! I NOTICED IT TOO!! and I was so flustered cause i ddnt know what to do...then just pretended it was 1mol/L LOL!
 

nichorowitz

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of course i still answered the question but i wrote the examiners a note.
they have given bonus marks in hsc exams before, hopefully if noone else wrote a note to the examiners i might receive one haha
 

zeebobDD

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it does matter, all the chemistry teachers at my school were complaining... though most students didnt even realise the mistake:S
 
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khorne

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Sometimes people like to pretend they are smart. Like this. The table does no specify the conditions. We know it's 1 mol/L but the table simply states "standard potentials". Thus, it is assumed valid for all concentrations for the purpose of the exam.
 

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