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failedmagician
06-23-2009, 10:04 PM
How many moles of AgIO3 (Ksp = 3.1 x 10^-8) will dissolve in one liter of a 10^-5 M solution of NaIO3?

I have an idea, but I want to see the thought process behind this one. Thanks.

nze82
06-23-2009, 10:21 PM
How many moles of AgIO3 (Ksp = 3.1 x 10^-8) will dissolve in one liter of a 10^-5 M solution of NaIO3?

I have an idea, but I want to see the thought process behind this one. Thanks.

AgIO3<-->Ag+ + IO3-

NaIO3 --> Na+ + IO3-

Ksp = [Ag+][IO3-]

3.1x10^-8 = [Ag+][10^-5]

[Ag+] = (3.1x10^-8)/(10^-5) = 3.1x10^-3M

M = n/L --> n = ML = (3.1x10^-3M)(1L) moles of AgIO3

failedmagician
06-23-2009, 10:31 PM
Thank you for your help. The answer is (3.1 x 10^-8)^1/2 - (10^-5)

So they took the square root of the ksp and then subtracted 10^-5.

I'm not sure that is the same thing as you have?

nze82
06-23-2009, 10:33 PM
Thank you for your help. The answer is (3.1 x 10^-8)^1/2 - (10^-5)

So they took the square root of the ksp and then subtracted 10^-5.

I'm not sure that is the same thing as you have?
Yea! Now I remember. I think there's another thread about this question. Doctoothache had some weird explanation about it. You might wanna search for it. I have no clue why they solve it like this. Is this from Achiever?