chemistry people..come in!!

[AS-Girl]

hi people

I got these 2 questions which i couldn't solve...the most important thing i need to know is the way of getting the answer!! so if anyone knows i would appreciate the help

I need the explanation of question 11 and 12!
scaned working out would be preferable hehe


Thanks in advance

[Deadly_king]

First you should write the equation showing the solubility of the salt.

In the first case it's Pb₂C₂O₄ -----> Pb²⁺ + C₂O₄^2-

Now you can write the K_sp

Ks_p = [Pb²⁺][C₂O₄^2-]

Since mole ratio of the two ions formed is 1:1, we can take it to be :

So K_sp = ² = 8.5 x 10^-9

Now you just have to find the value of .

I'll let you try the 2nd one yourself. If you can't do tell me and i'll try to be clearer

[AS-Girl]

Thanks deadly king

regarding the second question...i followed the same steps
so Ksp= Ag2CrO4------>2 Ag+  +  CrO4 (-2)

ratio moles is 2:1
so what happens next? im stuck here?!!

[Amelia]

Ag₂CrO₄ ---> 2Ag⁺ + CrO₄^2-

Solubility of CrO₄ = 3.2x10^-5
Solubility of Ag⁺ = 2 x 3.2x10^-5

Ksp = [Ag⁺]² [CrO₄]
Ksp = (2 x 3.2x10^-5)² (3.2x10^-5)
Calculate and you get the answer.

[AS-Girl]

Thanks Amelia

idea is cleared..if i got any other question..i'll surely post it here!!

Thanks again

[Amelia]

Thanks Amelia

idea is cleared..if i got any other question..i'll surely post it here!!

Thanks again

You are welcome.

[Deadly_king]

Ag₂CrO₄ ---> 2Ag⁺ + CrO₄^2-

Solubility of CrO₄ = 3.2x10^-5
Solubility of Ag⁺ = 2 x 3.2x10^-5

Ksp = [Ag⁺]² [CrO₄]
Ksp = (2 x 3.2x10^-5)² (3.2x10^-5)
Calculate and you get the answer.

Very well done my li'l princess

+rep

[Amelia]

Very well done my li'l princess

+rep

Thanks, daddy.