Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Qsp Calculations

  1. Feb 15, 2006 #1
    Calculate the ion product to determine if a precipitate will form when 125 mL .00500 M sodium chloride is mixed with 125 mL .00100 M silver nitrate solution.

    NaCl + AgNO3 -> NaNO3 + AgCl

    Net ionic equation = 2AgCl -> 2Ag + Cl2


    [Ag+] before = .00100 after = .00050
    [Cl-] before = .00500 after = .00250

    My question was about the Qsp. Would the Qsp = (.00050)(.00250) or Qsp = (.00050)^2(.00250) I don't understand which co-efficients to look at, the one in the equation or the one in the net-ionic equation. Thanks in advance for the help.
     
  2. jcsd
  3. Feb 16, 2006 #2
    Your question is very confusing.
    The 1st and 2nd equation are different...as well flipped in a way...

    you are saying one of the products is Chlorine gas... and the reactant is AgCl, which is a product of the first equation.
    the netionic eq qould be Cl(-) + Ag(+) --> AgCl, and i dont know why you are trying to balance it out.
    Remember its a solution, so you can have Cl(-) ions by themselves.

    Are you trying to find the reaction quotient??
     
  4. Feb 16, 2006 #3

    Borek

    User Avatar

    Staff: Mentor

    It is not a correct net ionic equation for this reaction. If you mix soluble silver salt with chlorides, silver chloride precipitates.
     
  5. Feb 17, 2006 #4
    why is it Cl(-) + Ag(+) --> AgCl ? don't you have to balance it out? i asked my teacher and she said to use the co-efficient from the net ionic equation
     
  6. Feb 18, 2006 #5

    Borek

    User Avatar

    Staff: Mentor

    And Cl- + Ag+ --> AgCl is the balanced net ionic equation of AgCl precipitation.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook