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Am I getting the correct answers for these Chemical Equilbium (I have a test tommorow

  1. Apr 21, 2005 #1
    Ive already done these problems and I think I'm doing them correctly, but I can't be 100% sure since I don't have the answers. Please help if you can since I have my test tommorow. Thanks

    Here are some of the questions

    1. If 2.6 moles of P4 and 3.6 moles of H2 are reacted till the following equilbirum is established P4 + 6H2 <===> 4PH3 , and if at equilbrium 1.6 moles of PH3 are formed, how many moles of P4 and H2 are in the equilibrium mixture?

    (I got .4 and 2.4)

    2. At 2000C k=6.2 x 10^-4 for the system N2 + O2 <==> 2NO. How many moles of N2 will exist in equilbrium in a 50 Liter box with .0062 mole of O2 and .0010 mole of NO?

    (I got .258 mole)

    3. If for the system NH4Cl (s) <=====> NH3 (g) + HCl (g) K=1.0 x 10^-4 . Find the moles of NH3 in a 100 liter container if initially there were 10.0 moles of NH3 added to 10 moles of HCl?

    (I got .1)
  2. jcsd
  3. Apr 22, 2005 #2


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    I got 2.2 and 1.2 moles for P4 and H2, resp. 0.4 and 2.4 moles are really present, but they are reacting amounts of them, so you will subtract these from the beginning amounts, i.e., 2.6 and 3.6 moles, resp.

    I don't have enough time to look at the remaining questions, sorry.
  4. Apr 22, 2005 #3


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    I'm not going to check all of your answers for you, you can correspond with the following and ask any questions.

    for the first question

    [tex]K= \frac{[2.6moles-x][3.6-6x]^{6}}{[4x]^{4}} [/tex]
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