Solve Ksp Equation for Sn^2+ When MnS Begins to Precipitate

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The discussion focuses on solving the Ksp equation for stannous sulfide (SnS) and manganese sulfide (MnS) as the sulfide ion concentration increases. The Ksp values are given as 1.0 x 10^-25 for SnS and 3.0 x 10^-15 for MnS. Participants are attempting to calculate the molar concentration of Sn^2+ when MnS begins to precipitate, with one user arriving at an incorrect concentration of 3.33E-9M instead of the correct 3.33E-13M. The confusion arises from miscalculations involving the sulfide ion concentration. Clarification is sought on the correct approach to reach the accurate answer.
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Homework Statement



For stannous sulfide, SnS, the Ksp = 1.0X10^-25
For manganese sulfide, MnS, the Ksp = 3.0 x 10^-15

Assume a solution contains .01 M Sn^2+ and .01 M Mn^2+. If the sulfide ion (S^2-) concentration is increased gradually without any dilution of the first solution, what will be the molar concentration of Sn^(2+) ion when manganese sulfide first starts to precipitate?

Homework Equations



Ksp = ?

The Attempt at a Solution



I've tried this question in what I, and a few of my friends who are stuck on it with me, consider a logical progression. I ended up with [Sn] = 1E-25, [Mn] = 3E-15, =1E-27 and =3E-17, respectively. [Sn][3E-17]=1E-15 and I end up with [Sn]=3.33E-9M. The answer is 3.33E-13 and I don't understand how it was attained. Any help is appreciated, thank you.
 
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0.01x10-17 is not 10-15.
 
Borek said:
0.01x10-17 is not 10-15.

Which part of my post are you referring to?
 
Anyone. You did the same mistake several times.
 
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