Nernst


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Ian Morris 3C
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Joined: Wed Sep 18, 2019 12:18 am

Nernst

Postby Ian Morris 3C » Wed Mar 04, 2020 7:21 pm

When should we use logQ vs lnQ.

Maya Beal Dis 1D
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Re: Nernst

Postby Maya Beal Dis 1D » Wed Mar 04, 2020 7:25 pm

If you are using the shortcut E=E(naught)-(0.05916/n)logQ, you need to use log. I think there is another number shortcut if you are using the equation with natural log.

605110118
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Re: Nernst

Postby 605110118 » Wed Mar 04, 2020 7:31 pm

Ln is easier and often used more.

Matt Sanruk 2H
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Re: Nernst

Postby Matt Sanruk 2H » Wed Mar 04, 2020 7:42 pm

Maya Beal Dis 1D wrote:If you are using the shortcut E=E(naught)-(0.05916/n)logQ, you need to use log. I think there is another number shortcut if you are using the equation with natural log.


Is this the equation given on the equation sheet?

Celine 1F
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Re: Nernst

Postby Celine 1F » Thu Mar 05, 2020 4:06 am

I don't think I saw the shortcut equation with .05916 on the equations sheet so I used Ln

Daria MacAuslan 1H
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Re: Nernst

Postby Daria MacAuslan 1H » Thu Mar 05, 2020 7:38 am

You usually use ln, just because it is more direct and it is also given to us on our equation sheets. If you want to use log however, just multiply by the conversion factor, it shouldn't really matter in the end

Katie Kyan 2K
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Re: Nernst

Postby Katie Kyan 2K » Thu Mar 05, 2020 10:34 am

You can use either but if you are trying to find the pH as in some of the HW problems, it would be easier to use the log version so you can find -log{H3O+].

Anthony Hatashita 4H
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Re: Nernst

Postby Anthony Hatashita 4H » Fri Mar 06, 2020 12:09 am

You can use either, the equation sheet lists both so whichever you are most comfortable using is best.

Diana Andrade_4F
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Re: Nernst

Postby Diana Andrade_4F » Fri Mar 06, 2020 1:12 am

You can use whichever you want to use!

Ying Yan 1F
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Re: Nernst

Postby Ying Yan 1F » Fri Mar 06, 2020 10:28 pm

When a problem is asking for you to solve for the pH or when you are given pH in a cell diagram, that's when you would usually use log instead of ln. Hope this helps!

205405339
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Re: Nernst

Postby 205405339 » Fri Mar 06, 2020 11:45 pm

lnQ can always be converted to logQ thru the equation: lnQ=2.303logQ


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