Chemistry 1120: Spring 2001 Semester
February 20, 2001
Class Worksheet 11 Key
1.
(a) What is meant by the term reaction rate?
The change in amount of product or reactant in a given amount of time.
(b) Name three factors that can affect the rate of a chemi
Chemistry 1120: Spring 2001 Semester
February 20, 2001
Class Worksheet 12 Key
1.
Suppose that the reaction A B and B A are both elementary processes with rate constants of 3.8 x 102 s-1
and 8.6 x 10-1 s-1, respectively.
(a) What is the value of the equili
Chemistry 1120: Spring 2001 Semester
February 20, 2001
Class Worksheet 12
1.
Suppose that the reaction A B and B A are both elementary processes with rate constants of 3.8 x 102 s-1 and 8.6 x
10-1 s-1, respectively. (a) What is the value of the equilibriu
CH 1120 Exam 1
Summer 03
1) The reaction that takes place in a Breathalyzer for determining the alcohol level in a
person's bloodstream is given below. If the rate of appearance of Cr2(SO4)3 is 1.24
mol/min, what is the rate of disappearance of C2H6O?
2 K
CH 1120 Exam 1
Summer 03
1) The reaction that takes place in a Breathalyzer for determining the alcohol level in a
person's bloodstream is given below. If the rate of appearance of Cr2(SO4)3 is 1.24
mol/min, what is the rate of disappearance of C2H6O?
2 K
CH 1120 Exam 1 Version A
October 2, 2002
1) The decomposition of dinitrogen pentoxide is described by the reaction below:
2 N2O5(g) 4 NO2(g) + O2(g)
If the rate of disappearance of N2O5 is equal to 1.40 mol/min, what is the rate of
appearance of NO2?
a) 0
CH 1120 Exam 1 Version B
October 2, 2002
1) The isomerization reaction, CH3NC CH3CN, is first order and the rate constant is
0.46 s-1 at 600 K. What is the concentration of CH3NC after 0.20 minutes of
reaction if the initial concentration is 0.10 M?
a) 9.
CH 1170 Exam 1
February 1, 2012
1. Which is the correct equilibrium constant expression for the following reaction?
Fe2O3(s) + 3H2(g) 2Fe(s) + 3H2O(g)
A)
B)
C)
Kc = [Fe2O3] [H2]3 / [Fe]2[H2O]3
Kc = [H2] / [H2O]
Kc = [H2O]3 / [H2]3
D)
E)
Kc = [Fe]2[H2O]3 /
CH 1120 Exam 2
Version A
November 6, 2002
1) Calculate the pH of a 0.20 M H2SO3 solution that has the stepwise dissociation constants of
Ka1 = 1.5 x 10-2 and Ka2 = 6.3 x 10-8.
a) 1.26
b) 1.32
c) 1.82
d) 2.52
Use Ka1 only in WA equilibrium ICE table. Need
CH 1170
Spring, 2012
Instructor: Dr. David Chesney
Office: Chem Sci 404C
Email: [email protected] (please put CH1170 in the subject line)
Lecture: MWF 11:00 AM
Chemical Sciences Room 101
Office hours: By appointment
Textbook: Chemistry by Chang 10th editio
CH 1170 Exam 3
April 4, 2012
1) In a conventional pH probe, what is the voltage difference expected for a 100
fold difference in H+ concentration (activity)?
A. 59 mV
B. It depends on the reference electr
CH 1100/1110 Exam 3
June 29, 2001
1. An "empty" aerosol can at 25oC still contains gas at 1.00 atmosphere pressure.
If an "empty" can is thrown into a 475oC fire, what is the final pressure in the
heated can?
a) 5.26 10-2 atm
b) 0.398 atm
c) 2.51 atm
d) 1
CH 1120 Exam 1
July 19. 2001
1. Which has the smallest dipole-dipole forces? a) CH3F b) HCl c) N2 d) CO 2. Which of the following compounds exhibits hydrogen bonding? a) CH3Cl b) HI c) H3C-O-CH3 d) NH3 3. Bromine is one of only two elements that is a liqu
Starting with 500.0 mL of 0.100 F acetic acid, how many mL of 2.00 F NaOH would
be required to create a buffer of pH 5.4?
(20.38 mL)
Starting with 500.0 mL of 0.100 F sodium acetate, how many mL of 1.70 F
CH 1170
Buffer problems, vol. 2
Consider using the following process for buffer calculations. As an example, I am
using the first problem from the previous worksheet:
Starting with 500.0 mL of 0.100 F acetic a
Note that ignoring the dissociation of the WA in the H-H
Equation is equivalent to using the Formal concentrations
Of the WA and its conjugate WB.
[HCOO-]
pH = pKa + log
[HCOOH]
0.30 x 0.30 = FHCOOCH
0.52 + x 0.52 = FHCOO[0.52] = 4.01
pH = 3.77 + log
[0.3
CH 1120 Exam 1 Fall 2002 Version A 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) 18) 19) 20) c) b) b) b) c) b) d) c) a) d) b) d) b) c) c) d) c) b) c) c)
CH 1120 Exam 1 Fall 2002 Version B 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) b) c) b
Question
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Answer
A
A
B
B
D
D
A
B
C
E
C
E
B
B
A
Questions 1 10 are worth 5 points each.
Questions 11 15 are worth 10 points each.
CH 1170 Exam 2
Feb 29, 2012
NOTE: Questions 1 10 are worth five points each.
1. In which one of the following solutions will acetic acid have the greatest percent
ionization?
A) 0.1 M CH3COOH
B) 0.1 M CH3COOH dissolved in 1.0 M HCl
C) 0.1 M CH3COOH plus 0
