Question

A sample of antimony pentachloride is sealed in a 250.0-cm3 glass bulb to which a pressure gauge is attached. The bulb is heated to 248 °C, and the gauge shows that the pressure in the bulb rises to 0.524 atm. At this temperature, the SbCl5(g) is partially dissociated into SbCl3(g) and Cl2(g) according to the equation SbCl5(g) SbCl3(g) + Cl2(g) At 248 °C, Kp = 1.07 for this reaction. Assume that the contents of the bulb are at equilibrium and calculate the partial pressure of the three different chemical species in the vessel.

PSbCl5 = ___atm

PSbCl3 = ___atm

PCl2 = _____atm

Answer 1

SbCl5(g) ------------->SbCl3(g) + Cl2(g) At 248 °C, Kp = 1.07

         SbCl5(g) ------------->SbCl3(g) + Cl2(g)

I         0.524                         0                0

C       -x                                +x              +x

E      0.524-x                       +x               +x

              Kp    = PSbCl3*PCl2/PSbCl5

             1.07   = x*x/(0.524-x

            1.07*(0.524-x) = x^2

     x = 0.385

PSbCl5   = 0.524-x   = 0.524-0.385   = 0.139atm

PSbCl3 = x             = 0.385atm

PCl2   = x              = 0.385atm