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Calculating percentage yield labi really need help?

  1. May 6, 2010 #1
    In this lab we saw the reaction of lead (II) nitrate with potassium iodide to form a lead (II) iodide precipitate and aqueous potassium nitrate.

    Pb(NO3)2 + 2KI ----> PbI2 + 2KNO3(aq)

    There was 3.31 grams Lead Nitrate, 1.66 grams Potassium Iodide, and 0.48 grams lead (II) iodide precipitate.

    What I need to know is the following (please show your work so I can learn how to do it.):

    Question #1: HOw many moles of PbI2 should be produced if the solutions are mixed?
    Question #2: What mass of PbI2 should be produced?
    Question #3: What is the theoretical yield of the precipitate and the percent yield of lead (II) iodide formed.

    Please help me!!!!
  2. jcsd
  3. May 7, 2010 #2


    User Avatar

    Staff: Mentor

    This is a very basic stoichiometry problem (limiting reagent problem to be more exact).

    Learn how to read balanced reaction equation, then on teh other pages you will find out how to calculate theoretical mass of teh product. basically you have to convert given masses to numbers of moles, calculate number of moles of product and convert it back to mass.

    Oh, and remember you have to use template and show your effort if you want to get help.

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