Respuesta :
Given question is incomplete. The complete question is as follows.
n-butane and isobutane are in equilibrium at 25 degrees centigrade.
    n-butane(g) [tex]\rightleftharpoons[/tex] isobutane(g)
A one liter flask with the two species at equilibrium contains 0.170 mole isobutane and 0.0680 mole n-butane. Then the concentration of n-butane is increase by 0.200 moles. (0.200 mole n-butane is added.) What is the new equilibrium concentration for isobutane.
Explanation:
As the given reaction is as follows.
      n-butane(g) [tex]\rightleftharpoons[/tex] isobutane(g)
Initial:     x                0
Equilbm: Â x - 0.17 Â Â Â Â Â Â Â Â Â Â 0.17
It is given that equilibrium concentration of n-butane is 0.068 M.
So, Â Â Â Â Â x - 0.17 = 0.0680
         x = 0.238
Therefore, the initial concentration is 0.238.
Here,
     [tex]K_{c} = \frac{[isobutane]}{[n-butane]}[/tex]
          = [tex]\frac{0.170}{0.068}[/tex]
          = 2.5
When 0.2 mol of n-butane is added. Hence, total moles will be as follows.
    Total mole = (0.238 + 0.2)
             = 0.438 mol
Hence, for 1 L volume the ICE table will be as follows.
      n-butane(g) [tex]\rightleftharpoons[/tex] isobutane(g)
Initial: Â Â 0.438 Â Â Â Â Â Â Â Â Â Â Â Â 0
Equilbm:  0.438 - x         x
          [tex]K_{c} = \frac{x}{0.438 - x}[/tex]
           2.5 = [tex]\frac{x}{0.438 - x}[/tex]
          1.095 - 2.5x = x
               x = [tex]\frac{1.095}{3.5}[/tex]
                = 0.3128 M
Thus, we can conclude that the equilibrium concentration is 0.3128 M.
