Chemistry

posted by .

A solution is 0.10M Pb(NO3)2 and 0.10M AgNO3. If solid NaCl is added to the solution what is [Ag+] when PbCl2 begins to precipitate? (Ksp PbCl2 = 1.7 x 10^-5; AgCl = 1.8 x 10^-10)

The answers is 1.4 x 10^-8

How do I find the answer

  • Chemistry -

    ......PbCl2(s) ==> Pb^2+ + 2Cl^-
    I......solid.......0.1.......0
    C......solid.........x.......2x
    E......solid.....0.1+x.......2x
    Ksp = (Pb^2+)(Cl^-)^2 = 1.7E-5


    .........AgCl(s)==> Ag^+ + Cl^-
    I........solid......0.1.....0
    C........solid......+x.......x
    E.........solid...0.1+x......x
    Ksp = (Ag^+)(Cl^-) =1.8E-10

    These are done this way.
    When NaCl is added, AgCl will ppt first because it has the smaller Ksp. It will continue pptng until the Ksp for PbCl2 is exceeded. What is the (Cl^-) when PbCl2 first ppts? That is
    1.7E-5 = (Pb^2+)(Cl^-)^2
    Substitute and solve for Cl^-. Remember Pb^2+ is 0.1M. I get something like 0.013 M but you need to confirm that.

    Then plug this Cl^- into Ksp for AgCl to find Ag^+ when PbCl2 just reaches that point.
    Ksp AgCl = (Ag^+)(Cl^-)
    1.8E-10 = (Ag^+)(0.013)
    Ag^+ = 1.8E-10/0.013 = 1.38E-8 M which rounds to 1.4E-8M

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. chemistry

    [Cl-] in PbCl2 solution, M? [Pb2+] in PbCl2 solution, M?
  2. Chemistry

    i need to find the; [Cl-] in PbCl2 solution,[Pb2+] in PbCl2 solution, and the ksp given: PbCl2(s)--> Pb2+(aq)+2Cl-(aq) Temp of solution =20.2 volume of Pbcl2 solution=25.00ml mass of dry AgCl2(g)=0.2543g #moles : AgCl(s)=1.77e-3 …
  3. chemistry

    If solid AgNO3 is slowly added to a solution that is .05 M in NaI and .12 M in NaCl, what is the concentration of I- when AgCl just begins the precipitate?
  4. AP Chemistry

    If .100 M NaCl (aq) is added slowly to a beaker containing both .120 M AgNO3 (aq) and .150 M Pb(NO3)2 (aq) at 25C which will precipitate first, AgCl(s)PbCl2(s)?
  5. chemistry (ionic eq.)

    what mass of Pb^2+ ion is left in solution when 50 ml of 0.2M PbCl2 is added to 50ml of 1.5 NaCl?
  6. Chemistry

    1 L of 0.002 mol/L Pb(NO3)2 has been prepared. Given that ksp for PbCl2 is 1.7 x10^-5, what is the largest number of moles of nacl that can be added to this solution without causing a precipitate to form.
  7. Chem

    Calculate the mass of PbCl2 formed when an excess of 0.100 M solution of NaCl is added to 0.4L of 0.7 M Pb(NO3)2. Pb(NO3)2 + 2 NaCl --> PbCl2 + 2 NaNO3
  8. Chemistry

    Silver chloride has Ksp=1.6x10^-10 and silver cheomate has Ksp=9.0x10^-12. We have 1.00 liter of a solution contains both nacl(0.10M) and Na2cro4(0.10M) solid AgNo3 is added slowly and the solution is stirred well. a) which precipitate …
  9. chemistry

    You have 310. mL of a 5.75×10-5 M Pb(NO3)2 solution. How many moles of NaCl must be added to precipitate a solid?
  10. Chem

    HCl is slowly added to a solution that is .250 M in Pb^2+ and .00150 M in Ag+. Which precipitate forms first, PbCl2 or AGCl?

More Similar Questions