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Solutions for The Study of Chemical Reactions
H
C
C
O
CH2CH3
O
CH
H
C N
H
CH
H
C N C NC
H
HH Base+
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32
Base +
34 (a) rate = k • [ CH O ] [C H Br] The reaction is first order in each, methoxide and 1-bromobutane.3
–
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(b) If the solvent is reduced by half with the same amount of reactants, the concentration of each doubles. 
Doubling the concentration of each will increase the rate by a factor of 4, i.e., four times faster.
∆H°
intermediate
Ea2
Ea1
transition states
en
er
gy
reaction coordinate
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products
reactants
(b) ∆H° is negative (decreases), so the reaction is 
exothermic.
(d) The first transition state determines the rate since 
it is the highest energy point. The structure of the 
first transition state resembles the structure of the 
intermediate since the energy of the transition state is 
closest to the energy of the intermediate.
(a) and (c)
transition stateactivation
energy
heat of reaction
reactants
products
reaction coordinate
en
er
gy
36
37
reaction coordinate
en
er
gy
energy of highest transition state
determines rate
∆H° is positive
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The rate law is first order with respect to the concentrations of hydrogen ion and of tert-butyl alcohol, 
zeroth order with respect to the concentration of chloride ion, second order overall.
rate = kr [(CH3)3COH ] [ H + ]
Ea
∆H°
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