## Why is Ka the square root of K

$\Delta G^{\circ} = -nFE_{cell}^{\circ}$

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

### Why is Ka the square root of K

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

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

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