|
|
In the reaction NH4+ + NO2- → N2 + 2
H2O, which had this rate law:
k[NH4+][NO2-]
it isn't difficult to imagine that the
concentrations of either reactant might have the same effect on
the rate. After all, they are in a 1:1 ratio in the balanced
equation. But a study of just a few rate laws will show that this
is an erroneous connection. In fact, except for the very simplest kinds of reactions the orders in the rate law are generally only
coincidentally related to the coefficients in the balanced
equation.
The rate law for the second
reaction, NO2 + CO →
NO + CO2, which was
k[NO2]2, is interesting because it tells us
that the concentration of CO is not a factor in the rate and the
concentration of NO2 is important out of proportion to
its appearance in the balanced equation. How can this be?
|
