The reaction described by H2(g) + I2(g) yields
2HI(g)
has an experimentally determined rate law of
rate of reaction= k [H2] [I2]
some proposed mechanisms for this reaction are:
Mechanism a.
1. H2(g) + I2(g) yields (k1 on top of the arrow) 2HI
(g) (one step reaction)
Mechanism b.
(1) I2(g) equilbrium arrow (k1 on top of the arrow, and k-1 on
the bottom of the arrow ) 2I (g) (fast equlibrium
)
(2) H2(g) + 2I(g) yields (k2 on top of the
arrow) 2HI(g) (slow)
Mechanism c.
(1) I2(g) equlibrium arrow (k1 on top of the
arrow, k-1 on the bottom of the arrow) 2I(g)
(2) I(g) +H2(g) equlibrium arrow (k2 on the top and
k-2 on the bottom of the equilibrium arrow) yields
H2I(g) (Fast equlibrium)
(3) H2I(g) yields ( k3 on top of the
arrow) HI(g) + I(g) (slow)
a) which of these mechanisms are consistent with the observed
rate law?
mechanism a
mechanism b
mechanism c
b) in 1967 J.H Sullivan showed that this reaction was
dramtically catalyzed by light when the energy of the
light was sufficent to break the I-I bond in an I2 molecule. Which
mechanism(s) are consistent with both the rate law and this
additional observation?
Mechanism a
Mechanism b
mechanism c
Answer
