Page 144 - Elements of Chemical Reaction Engineering 3rd Edition

116 Rate Laws and Stoichiometry Chap. 3

The bottom-most temperature of the column is approximately 125°C
and the topmost is 100°C. The corrosion rate is a function of temperature and
the concentration of a HCN-H2S04 complex. Suggest an explanation for the
observed corrosion plate profile in the column. What effect would the column
operating conditions have on the corrosion profile?
P3-5, The rule of thumb that the rate of reaction doubles for a 10°C increase in tem-
perature occurs only at a specific temperature for a given activation energy.
(a) Develop a relationship between the temperature and activation energy for
which the rule of thumb holds. Neglect any variation of concentration
with temperature.
(b) Determine the activation energy and frequency factor from the following
data:
0.001 0.050

P3-6A In each of the following reactions determine the specific reaction rate constant
for each of the other species in the reaction. Assume that kA in each case has
a value of 25 with the appropriate combination of units of mol, dm3, g cat, and s.
(a) For the reaction

2A+B ---+ C
the rate law is -rA = kACiCB. (Partial ans.: For kA = 25 dm6/mo12*s,
kc = kAf2 = 12.5 dm6/moI2. s and r, = 12.5 tic,.)
(b) For the reaction
~A+;B --+ c

the rate law is -rA = kAcAcB.
(c) For the solid catalyzed reaction
4A+5B __j 4C-C 6D
the rate law is -ra = kAcicB (see Problem 3-13) [kD = ?, kB = ?I.
(d) In the homogeneous gas-phase reaction

CH4 + O2 ---+ HCOOH + H,O
What is the relationship between rCHq and Yo2 ?
rCH4 = '02
(2) Cannot tell without the data
(3) 'CH4 =
(4) rCH4 = ir02
(5) None of the above
P3-7, Set up a stoichiometric table for each of the followin4 reactions and express
the concentration of each species in the reaction as a function of conversion
evaluating all constants (e.g., E , 0).
(a) The liquid-phase reaction
CHZ-OH
/"\ I
CH,-CHZ + HZO H2s04> CH,-OH