1. Guest, be sure to check out How To Get Into Dental School, our free downloadable PDF with step-by-step details for dental school applicants!
    Dismiss Notice

Gen Chem Question from Kaplan

Discussion in 'Pre-Dental' started by esperi, Apr 17, 2007.

  1. esperi

    esperi New Member

    Joined:
    Feb 26, 2004
    Messages:
    6
    Likes Received:
    0
    Question from Kaplan Practice Test:

    How many moles of AgIO3 (Ksp=3.1x10^-8) will dissolve in 1 Liter of a 10^-5 M solution of NaIO3?

    a. sqrt(3.1x10^-8)
    b. [sqrt(3.1x10^-8)] [10^-5]
    c. [sqrt(3.1x10^-8)] / [10^-5]
    d. [10^-5] - [sqrt(3.1x10^-8)]
    e. [sqrt(3.1x10^-8)] - [10^-5]

    Kaplan says the answer is E, but I don't get why.

    I get how Ksp=[Ag+][IO3-]= X^2= 3.1x10^-8, thus X= sqrt(3.1x10^-8). But why subtract [10^-5] from it ??? Anyone care to explain? Would appreciate it very much!
     
  2. Thread continues after this sponsor message. SDN Members do not see this ad.

  3. DentalBoston

    DentalBoston Dental Student

    Joined:
    Apr 17, 2007
    Messages:
    6
    Likes Received:
    0
    Status:
    Dental Student
    It's been a while sine I've done any general chem but since IO3 is a common ion in both you have to take that into account by subtracting the 10^-5. I'm sure if you have a chem book you can review the entire idea by looking up common ion effect.
     

Share This Page