If we begin with equal of reactants
and products,
the forward reaction will be faster than the reverse because e-3.61/RT
is greater than e-85.7/RT.
More products will accumulate.
equilibrium,
defined by ratef = rater,
will not be reached until the excess of products is great enough
to compensate for the larger forward rate
constant, which is a consequence of the smalleractivation
energy of the forward reaction.
The equilibrium
constant, which is the ratio of products to reactants at equilibrium,
therefore will be larger than 1.00. If the products are thermodynamically
less stable than reactants (positive DH0
of reaction), then the reverse rate
constant will be greater than the forward, equilibrium will
be attained with an excess of reactants, and Keq
will be less than 1.00. Both situations are diagrammed opposite.
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