Chemistry

posted by .

At 400°C the reaction H2+I2<->2HI has an equilibrium constant Kp value of 55.5. A mixture of 1 mole of H2 and 1 mole of I2 is placed in a flask and heated to 400°C. Calculate the mole fraction of HI in the mixture of gases when equilibrium reached.

  • Chemistry -

    55.3=(2x)^2/(1-x)^2

    solve for x Use the quadratic equation

  • Chemistry -

    i don't understand bobpursley..how is it actually?

  • Chemistry -

    H2 +I2---> 2HI.

    The equilibrium expression is

    Kp = reactants/products=[2HI]^2/[H2][I2]

    Since you have 2 moles of HI for every mole of H2 or I2, you square the products.


    You start off with 1 mole of H2 and I2, and some, not all of the reaction produces x amount of HI. You don't know how much, but you know the molar ratio of HI will be twice as much as H2 or I2, so that is why he told you (2x)^2 for the product. Since the amount of HI is subtracted from the initial concentrations of H2 and I2 to make HI, the amount subtracted is 1-X for each. Looking at the equation that I gave you above, you will see that reactants are multiplied by each other to produce (1-x)^2. The rest is just using algebra to solve for x, and the only way that you can do that is to use the quadratic equation.


    I hope this helps.

  • Chemistry -

    Its helps a lot...btw are you assuming Kp=Kc?

  • Chemistry -

    Yes.

  • Chemistry -

    Sorry for asking such simple question. Why we must assume like that? And why not the Kp= [HI]^2/[H2][I2]?Yet you put 2 in front of HI. Typo?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    At a particular temperature, k=1.6x10^-5 for the reaction 2SO3(g)=2SO2(g)+ O2 If 4 mole of SO2 and 2 mole of O2 are placed into a 2.0 L flask, calculate the equilibrium concentration of all the species. Thanks.
  2. chemistry

    i already posted this question, but im still confused on it. Dinitrogentetraoxide partially decomposes according to the following equilibrium: N2O4 (g) -> 2NO2 (g) <- A 1.00-L flask is charged with 0.400 mol of N2O4. At equilibrium …
  3. Chemistry

    One mole of N2 and three moles of H2 are placed in a flask at 375 C. Calculate the total pressure of the system at equilibrium if the mole fraction of NH3 is 0.21. The Kp for the reaction is 4.31*10^4. I assume this to be the reaction …
  4. Chemistry

    One mole of N2 and three moles of H2 are placed in a flask at 375 C. Calculate the total pressure of the system at equilibrium if the mole fraction of NH3 is 0.21. The Kp for the reaction is 4.31*10^4. I assume this to be the reaction …
  5. chemistry

    Ammonium bisulfide, NH2HS, forms ammonia NH3, and hydrogen sulfide, H2S through the reaction: NH4HS (s) <--> NH3(g) + H2S(g) Kp value of .120 at 25C in a 5L flask is charged with .300g of H2S at 25C. A) What are the partial pressures …
  6. science-chemistry

    please anwser soon, a rigid 4.10L flask contains a mixture of 1.25 moles of H2, 0.250 mole of O2, and sufficient Ar so that the partial pressure of Ar in the flask is 1.00 atm. The temperature is 63.5 degrees C A) Calculate the total …
  7. chemistry

    c. A student put 1.18 mole of substance A and and 2.85 mole of substance B into a 10 litre flask which was then closed. The reaction that took place was: A(g)+ 2B(g) 3C(g) + D(g) On analysis the equilibrium mixture at 25 0 C was found …
  8. Chemistry

    At the start of the reaction there are 0.714 mole of H2, 0.984 mole of I2, and 0.886 mole of HI in a 2.70 L reaction chamber. Calculate the concentrations of the gases at equilibrium.
  9. Chemistry

    At the start of the reaction there are 0.714 mole of H2, 0.984 mole of I2, and 0.886 mole of HI in a 2.70 L reaction chamber. Calculate the concentrations of the gases at equilibrium. The equilibrium constant is 54.3.
  10. Chemistry

    One mole of N2 and 3 moles of H2 are placed in a flask at 375 degree celsius.?

More Similar Questions