Why is Ka the square root of K


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Denise 3L
Posts: 13
Joined: Fri Sep 26, 2014 2:02 pm

Why is Ka the square root of K

Postby Denise 3L » Tue Feb 10, 2015 6:54 pm

Hi, I was working in Q8. on the 2014 midterm and to solve for Ka they took the K value they found and took the square root of it. Why is this?

K Honeychurch 1K
Posts: 27
Joined: Fri Sep 26, 2014 2:02 pm

Re: Why is Ka the square root of K

Postby K Honeychurch 1K » Tue Feb 10, 2015 7:18 pm

When you calculated K for the redox reaction you were calculating [H+]2[F-]2/[HF]2 because the coefficients of the balanced redox reaction were 2 for H+, F-, and HF. However, Ka=[H+][F-]/[HF]. So, Ka=square root K.

LeilaBushweller1F
Posts: 12
Joined: Fri Sep 26, 2014 2:02 pm

Re: Why is Ka the square root of K

Postby LeilaBushweller1F » Tue Feb 10, 2015 8:33 pm

Further, you cannot simply divide the reaction by two (to get a coefficient of 1 for everything), since the cell potential (E) would then be for a different equation (and you cannot simply divide the cell potential by two).

Sarah H Brown 1L
Posts: 56
Joined: Fri Sep 26, 2014 2:02 pm

Re: Why is Ka the square root of K

Postby Sarah H Brown 1L » Tue Feb 10, 2015 9:51 pm



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