How to get 15% here (the right answer)?
ZnCl
2 Zn
2++2Cl
-I calculated the degree: n(ZnCl
2 that dissociated)/n(ZnCl
2 at the beginning)*100 and got 13%.
n(ZnCl
2 that dissociated) is equal to n(Cl
-)/2.
n(ZnCl
2 at the beginning) is equal to n(ZnCl
2 that dissociated) + n of the undissociated salt.
It can't be a mistake in calculation.