[quntum]

hey, i'm uncertain about my solutions to these solubility problems. can someone help me out here? the first 2 questions i used the way that my text book uses, but i'm just not 100% positive that i did it correctly. The other 2 i also used the text book, but i'm not quite sure how i came up with the answer. The solutions seemed too short for the answer to b correct.

1)a 0.050mL drop of 6.0mol/L hydrochloric acid is added to 1.0L of a 0.10mol/L aqueous silver nitrate solution. Can we expect a precipitate for silver chloride to form? The K_sp for silver chloride is 1.6 x 10^-10.

my answer is it will because Qsp > Ksp

2)A student wished to prepare 1.0L of a solution containing 0.015 mol of NaCl and 0.15 mol of Pb(no₃)₂. She was concerned that a precipitate of PbCl₂ might form. The Ksp of PbCl₂ is 1.7 x 10^-5. Can she expect to observe a precipitate of PbCl₂ in the mixture?

my answer is it will because Qsp > Ksp

3)What is the molar solubility of PbI₂ in a 0.10M NaI solution? K_sp for PbI₂ is 7.9 x 10^-9.

my answer 7.9 x 10^-7

4)The molar solubility of PbCl₂ in a 0.10M NaCl solution is 1.7 x 10^-3mol/L. What is the K_sp  for PbCl₂?

my answer is 0.17 mol/L

any help would be greatly appreciated!!

THX!

[Borek]

First two OK. Then you are wrong.

How do you calculate concentrations of ions present in the solution above solid when given Ksp and the solid is the only source of ions? Hint: you need Ksp and stoichiometry to do that.

[AWK]

3 is also OK