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CHM 112
Section 1

Homework Assignment #3
Due January 30, 2006 by 8:05 a.m.

Practice (not to be turned in): 13.27, 13.30, 13.32, 13.33, 13.34, 13.38, 13.40, 13.41, 13.47, 13.48


Consider the reaction

A(g) products

Choose the data set corresponding the to last digit in your Student ID Number.

Plot the data as:
a) a zero order reaction
b) a first order reaction
c) a second order reaction

Based on these plots, determine the order of reaction and the rate constant, including units. Use a full, clean sheet of graph paper for each plot (spread sheets plots are NOT acceptable). Be sure that the axes are labeled and that the data uses the entire plotted area of your graph.


data set 0
time (s)
[A]
0.00
0.100
0.10
0.086
0.20
0.074
0.30
0.064
0.40
0.055
0.50
0.047
0.60
0.041
0.70
0.035
0.80
0.030
0.90
0.026
1.00
0.022


The first order plot is linear with a slope = –1.5 so the rate constant k = 1.5 s–1


data set 1
time (s)
[A]
0.000
0.100
0.005
0.090
0.010
0.080
0.015
0.072
0.020
0.064
0.025
0.058
0.030
0.052
0.035
0.046
0.040
0.041
0.045
0.037
0.050
0.033


The first order plot is linear with a slope = –22 so the rate constant k = 22 s–1


data set 2
time (s)
[A]
0.0000
0.100
0.0010
0.090
0.0020
0.081
0.0030
0.072
0.0040
0.065
0.0050
0.058
0.0060
0.052
0.0070
0.047
0.0080
0.042
0.0090
0.038
0.0100
0.034


The first order plot is linear with a slope = –108 so the rate constant k = 108 s–1


data set 3
time (s)
[A]
0.00
0.100
0.10
0.088
0.20
0.078
0.30
0.070
0.40
0.064
0.50
0.059
0.60
0.054
0.70
0.051
0.80
0.047
0.90
0.044
1.00
0.042


The second order plot is linear with a slope = +14 so the rate constant k = 14 M–1 s–1


data set 4
time (s)
[A]
0.000
0.100
0.010
0.082
0.020
0.069
0.030
0.060
0.040
0.053
0.050
0.048
0.060
0.043
0.070
0.039
0.080
0.036
0.090
0.033
0.100
0.031


The second order plot is linear with a slope = +224 so the rate constant k = 224 M–1 s–1


data set 5
time (s)
[A]
0.0
0.100
1.0
0.081
2.0
0.068
3.0
0.058
4.0
0.051
5.0
0.045
6.0
0.041
7.0
0.037
8.0
0.034
9.0
0.032
10.0
0.029


The second order plot is linear with a slope = +2.4 so the rate constant k = 2.4 M–1 s–1


data set 6
time (s)
[A]
0.0000
0.100
0.0025
0.092
0.0050
0.084
0.0075
0.076
0.0100
0.068
0.0125
0.060
0.0150
0.052
0.0175
0.044
0.0200
0.036
0.0225
0.028
0.0250
0.020


The zero order plot is linear with a slope = –3.2 so the rate constant k = 3.2 M s–1


data set 7
time (s)
[A]
0.000
0.100
0.025
0.092
0.050
0.083
0.075
0.075
0.100
0.066
0.125
0.058
0.150
0.049
0.175
0.041
0.200
0.032
0.225
0.024
0.250
0.015


The zero order plot is linear with a slope = –0.34 so the rate constant k = 0.34 M s–1


data set 8
time (s)
[A]
0.00
0.100
0.50
0.092
1.00
0.084
1.50
0.076
2.00
0.068
2.50
0.060
3.00
0.052
3.50
0.044
4.00
0.036
4.50
0.028
5.00
0.020


The zero order plot is linear with a slope = –0.016 so the rate constant k = 0.016 M s–1


data set 9
time (s)
[A]
0.00000
0.100
0.00025
0.089
0.00050
0.079
0.00075
0.070
0.00100
0.062
0.00125
0.055
0.00150
0.049
0.00175
0.043
0.00200
0.038
0.00225
0.034
0.00250
0.030


The first order plot is linear with a slope = –483 so the rate constant k = 483 s–1