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Question:

layn
layn
Student
High School - 12th Grade

if k=1.00x10^-4 for the reaction

N2(g)+O2(g)_________ 2NO(g)

find the number of moles of NO in a 10.0L container if the intial (N2)and (O2)is 1.00mol/L.

pl i need this answer now thankyou

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Posted by layn on Tuesday March 3, 2009 at 4:18 PM and tagged with science.


Answers:

  1. doabbott3
    doabbott3 Teacher
    Graduate School

    eNotes Editor

    Amazing.... I assume this answer is much too late; however, for posterity (and to prove myself?); here goes.... (I might mention that simply doing the problem for you may have very little impact on your learning to do it yourself; you should try, hard, to do as much as you can BEFORE you ask...?)

    The general equilibrium equation constant, (1X10^-4) is equal to the mathematical product of the concentration of products [NO] , in mole/L, raised to the respective power of their coefficients, 2; Divided by the product of the concentrations of the reactants, [N2] & [O2] raised to the respective power of their coefficients:  

    1X10^-4 = [NO]^2/ {[N2][O2]}

    Initial Concentrations of N2 and O2 = 1M; NO= 0M

    If X amount of N2 and O2 react then:

    Equilibrium concentrations of N2 and O2 = [1-X]

    Equilibrium concentration of NO = 2X

    So since 1X10^-4 is small; not much reacts so "X" is gonna be small; therefore [1-X] =~1

    Therefore: 1X10^-4 = [2X]^2 /{[1][1}

    and 1X10^-4 = 4X^2 or 1X10^-4 /4 = X^2 or 25X 10^-6 = X^2 or 5X10^-3 = X so [NO] = 2X = [1X10^-2]

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    Posted by doabbott3 on Friday October 9, 2009 at 9:39 PM