1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Entropy and Equilibrium Constant

  1. Apr 11, 2006 #1
    Calculate Ksp for PbI2 at 25 C based on the following data:
    SPECIES------------deltaG_f kJ/mol
    Pb (2+) (aq) -------(-)24.4
    I- (aq)-------------(-)51.6
    PbI2 (s)------------(-) 173.6



    a. 4 x 10-31
    b. 8 x 10-18
    c. 9 x 10-9
    d. 5 x 10-5

    PbI2 <-> Pb (2+) + 2I-

    Use G_f = sigma prod. - sigma reactants

    [2(-51.6) - 24.4]kJ - [-173.6]kJ

    G_f = 46 kJ = 4.6E3 J

    ln K = -G/RT
    K = e^-(4.6E3/(8.314*298.15 K) = 8.72E-9

    Thanks.
     
  2. jcsd
  3. Apr 11, 2006 #2

    siddharth

    User Avatar
    Homework Helper
    Gold Member

    Your approach to solve this problem looks right.

    That looks like a mathematical error.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...