Acid/Base Q

[PremedicalS]

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Explain why both KOH and KOAc would have the same conductances when added in same concentration and same volume to water.

-Both KOH and KOAc are salts comprised of an anion and a cation, so thus will both completely dissociate into water, resulting in the same ion concentration in both solutions. The electrical conductivity depends on the number of ions in solution, not the strength of the species in solution.

Can someone please explain this to me? KOH is a strong base, and KOAc is a weak base, and a I am having trouble understanding why this answer is true. Thanks very much in advance.

 

[Pose]

I'm not sure, but this reminds me of the the Van't Hoff factor. Conductivity depends not on the strength of the species, but just the concentration of ions present. I guess they both dissociate into two parts, therefore have the same conductivity. KOH would turn into K+ and OH-, and KOAc would dissociate into K+ and OAc-.

KOAc isn't just a weak base, it's a salt that happens to be basic.

 

[Incontrol]

Both dissociate COMPLETELY in water, which means if you throw one mole of KOH in water you will have 1 mole of K+ and one mole of OH-, and if you throw 1 mole of KOAc you will have one mole of K+ and one mole of -OAc. Since conductivity only cares about the amount of charge in solution and not by their qualities (acid/base); they will have the same conductivity.

KOH is a stronger base than KOAc not because KOH dissociates more readily than KOAc. But its because the nature of the molecule -OAc is not a very strong base compared to -OH

In another note: 1 mole of HCl vs 1 mole of NaOH both have the same conductivity because all of them completely dissociate in water. (has nothing to do with acid vs base).