In: Chemistry
A student ran the following reaction in the laboratory at 720 K: H2(g) + I2(g) 2HI(g) When she introduced 0.189 moles of H2(g) and 0.218 moles of I2(g) into a 1.00 liter container, she found the equilibrium concentration of I2(g) to be 6.05×10-2 M. Calculate the equilibrium constant, Kc, she obtained for this reaction. Kc =
H2(g) + I2(g) <=====> 2HI(g)
I 0.189 0.218 0
C -x -x 2x
E 0.189-x 0.218 -x 2x
but he has given equilibrium concentration I2 = 0.0605
0.218 -x = 0.0605
x = 0.218 - 0.0605 = 0.1575
[H2] = 0.189-x = 0.189 - 0.1575 = 0.0315 M
[HI] = 2x = 2 x 0.1575 = 0.315
Kc = [HI]2 / [H2] [I2]
Kc = [0.315]2 / [0.0315] [ 0.0605]
Kc = 0.099225 / 0.00190 = 52.066