Chemistry

posted by .

A researcher is studying the decomposition of A as shown by the general reaction below:

2 A(g) 4 B(g) + 2 C(g)

Initially, the scientist fills an evacuated 1.772 L flask with 3.710 x 10-1 moles of species A. Upon equilibrium, it is determined that the concentration of A is 4.606 x 10-2 M. Calculate Kc.

This is what I have done:

2A ---> 4B + 2C
I: 3.710E-2 mol --> 0 M + 0 M
2.094E-1 M ---> 0 M + 0 M
C: -1.633E-1 ---> +_______ + ________
E: 4.606E-2 M ---> _______ + ________

Kc= ([B]^4[C]^2)/((4.606E-2)^2)

  • Chemistry -

    You're ok with 0.2094M to start and 1.633 M change and 0.04606 Equil but it stops there. Here is what you do. By the way, note how I get around the spacing problem.You also need to note the arrow.
    ............2A ==> 4B + 2C
    initial..0.20937....0.....0
    change......-2x.....4x....2x
    equil......0.04606..........
    2x = 0.20937-0.04606 = 0.16331
    Therefore, x = 0.16331/2 = 0.08165M
    Then equil B = 4x and equil C = 2x.
    Substitute those into Kc expression and solve.
    I carried more places than allowed by the significant figure rules; you can round as your instructor does. I round at the end.

  • Chemistry -

    Thank you Dr. Bob.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. chemistry

    An equilibrium mixture of SO2,SO3 and O2 gases is maintained in a 11.5 L flask at a temp at which Kc=55.2 for the rxn shown below. If the number of moles of SO3 in the flask at equilibrium is twice the num of moles of SO2, how much …
  2. Chemistry-w/addition

    At elevated temperatures, SbCl5 gas decomposes into SbCl3 gas and Cl2 gas as shown by the following equation: SbCl5(g)<=> SbCl3(g) + Cl2(g) (a) An 59.8 gram sample of SbCl5 (molecular weight 299.0) is placed in an evacuated 15.0 …
  3. Chemistry

    Consider three 1.0 L flasks at 25° C and 96.66 kPa containing the gases CH4 (flask A), CO2 (flask B), and C2H6 (flask C). In which flask is there 0.039 moles of gas?
  4. Chemistry

    The reaction describing the formation of ozone from oxygen is shown below. 3 O2(g) <--> 2 O3(g) Calculate Grxn at 288 K for this reaction in a flask where [O2] = 3.419 x 10-2 M and [O3] = 5.783 x 10-4 M. Assume G° = 326 kJ. …
  5. Chemistry - Kp

    What is the Kp for the following reaction: 2NH3(g) --> N2(g) + 3H2(g) This reaction is contained in 1.0 L container at 1,000 K and has reached equilibrium. (Kc = 4.0 x 10^-2). You have initially added 1,220 moles of NH3(g) in the …
  6. Chemistry - Kp

    What is the Kp for the following reaction: 2NH3(g) --> N2(g) + 3H2(g) This reaction is contained in 1.0 L container at 1,000 K and has reached equilibrium. (Kc = 4.0 x 10^-2). You have initially added 1,220 moles of NH3(g) in the …
  7. Chemistry

    Calculate the degree of freedom of NH4Cl, initially in an evacuated chamber, with NH3 & HCl present from decomposition.
  8. Chemistry

    A sample of gaseous PCl5 was introduced into an evacuated flask so that the pressure of pure PCl5 would be 0.54 atm at 425 K. However, PCl5 decomposes to gaseous PCl3 and Cl2, and the actual pressure in the flask was found to be 0.85 …
  9. Chemistry

    Which of the following general equations describes all decomposition reactions?
  10. Chemistry

    A flask of known volume was filled with air to a pressure of 3.6atm. This flask was then attached to an evacuated flask of known volume and the air was allowed to expand into the flask. The final pressure of the air (in both flasks) …

More Similar Questions