Which of the following mixtures will result in the formation of a precipitate of Ag_2SO_4?

We have the following four solutions:
A [Ag^+] = 1e-4
B [Ag^+] = 3e-8
C [SO_4^-2] = 6e-3
D [SO_4^-2] = 5e-7

K_sp for Ag_2SO_4 = 2.93e-13

A + C
A + D
A + B
B + C
B + D

1 Answer
Dec 10, 2017

Well, what is the ion product Q in each case....?

Explanation:

We address the equilibrium...

2Ag^+ +SO_4^(2-) rarr Ag_2SO_4(s)darr

Now K_"sp"=[Ag^+]^2[SO_4^(2-)]...and this is simply an equilibrium expression. And all we have to do is calculate the ion product....Q=[Ag^+]^2[SO_4^(2-)].

If [Ag^+]^2[SO_4^(2-)]>K_"sp" then precipitation will occur...

If [Ag^+]^2[SO_4^(2-)]<=K_"sp" then the sulfate will remain in solution. I will do the first and then you are on your own....

We try A.+C., [Ag^+]=1xx10^-4*mol*L^-1; [SO_4^(2-)]=6xx10^-3*mol*L^-1.

The ion product, Q=(1xx10^-4)^2xx(6xx10^-3)=6.0xx10^-11.

Now Q">>"K_"sp"=2.93xx10^-13...and so precipitation will occur.

And now you use the same procedure on all the other examples. You could post them here....