In: Chemistry
The following reaction was performed in a sealed vessel at 742 ∘C :
H2(g)+I2(g)⇌2HI(g)
Initially, only H2 and I2 were present at concentrations of [H2]=3.50M and [I2]=2.00M. The equilibrium concentration of I2 is 0.0900 M . What is the equilibrium constant, Kc, for the reaction at this temperature?
H2(g) + I2(g) <---------------------------> 2HI(g)
3.50 2.00 0 ----------------------> initial
3.50-x 2.00-x 2x ----------------------> equilibrium
but equilibrium concentration of I2 is 0.0900 M is given so
2.00 - x = 0.09
x = 1.91
equilibrium concentrations :
[H2] = 3.50 - x = 3.50 -1.91 = 1.59 M
[I2] = 0.09 M
[HI] = 2x = 2 x 1.91 = 3.82 M
Kc = [HI]^2 / [H2] [I2]
Kc = (3.82)^2 / (1.59) (0.09)
Kc = 102