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: Applications of Equilibrium Constants

  1. Jan 16, 2010 #1
    1. The problem statement, all variables and given/known data

    At 1285*C the equilibrium constant for the reaction [tex]Br_2 (g) \Leftrightarrow 2Br (g)[/tex]. A 0.200L vessel containing an equilibrium mixture of the gasses has 0.245g of [tex]Br_2[/tex](g) in it. What is the mass of Br(g) in the vessel?

    2. Relevant equations

    None

    3. The attempt at a solution

    I have tried this 4-5 different ways at least and cannot get close to the answer. I started with this

    [tex]K_c = \frac{[Br]^{2}}{[Br_2]}[/tex]

    Rearrange that to solve for Br. I get...

    [tex][Br_2] \times K_c = [Br]^2[/tex]

    Then after that I am lost. I've tried converting Br_2 from grams to moles. Leaving it as grams and converting at the end. The answer in the book is in M, but I cannot even come close to that.

    Any hints? I know for sure just plugging in grams of Br_2 and K_c, then solving for x doesn't get me even in the ballpark.

    The book answer is 0.00767M. Which strangly enough is what I get what I convert 0.245g of Br_2 into M.

    The answer I get at the end is 0.0028 M Br.



    EDIT!! Nevermind. I am a moron. I had the answer right the whole time I just wasn't reading the answer book correctly. :blushing:
     
    Last edited: Jan 16, 2010
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted