Problems
7.1 What are the units for the rate of a chemical reaction?
7.2 For a reaction A ↔B that has an equilibrium constant of 10, what can be said about the rates?
7.3 For the irreversible reaction A →B, what effect will doubling the concentration of B have
on the rate of change of A?
7.4 The time dependence of the conversion of a substrate by an enzymatic reaction is charac-
terized by a half-life of 150 s. How long is required for the concentration of the substrate
to decrease from 16 to 1 nM?
7.5 The time dependence of the conversion of a substrate by an enzymatic reaction is charac-
terized by a rate of 0.0046 s−^1. How long is required for the concentration of the substrate
to decrease from 16 to 1 nM?
7.6 Initially a system has species A at a concentration of 0.1 M. If a process proceeds from A
to both B and C in parallel first-order reactions, and the two forward rates are identical,
what are the final amounts of species B and C?
7.7 Initially a system has only species A at a concentration of 0.1 M. If a process proceeds from
A to both B and C in parallel first-order reactions, and the forward rate to produce B is ten
times larger than the rate to produce C, what are the final amounts of species B and C?
CHAPTER 7 KINETICS AND ENZYMES 161
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