chemistry
Problem Set II
Chapters 16, 17, 18
Please complete the following questions on separate, lined paper. Organize the questions in the order they are given here, making sure to box/circle all answers and use appropriate units when necessary. Some questions may require you to use a calculator or research necessary information. This information should usually be easily found within the text or a quick web search.
You may complete this assignment using any assistance necessary, including any other individuals (professors, tutors, students, etc.). However, all work must be shown for every problem, and every student must turn in their own assignment. Working in groups is acceptable, so long as every student produces their own set of responses to turn in.
————————————————————————————————
Chapter 16
1.) For the reaction below, the following data were obtained at a constant temperature:
4 A (g) + 3 B (g) 2 C (g)
Trial Initial Rate (mol/L•min) Initial [A]
(mol/L) Initial [B]
(mol/L)
1 1.29 x 10-29 1.00 0.100
2 1.33 x 10-30 0.100 0.100
3 1.30 x 10-29 0.100 1.00
4 1.32 x 10-31 0.100 0.0100
a. What is the rate law for the formation of C?
b. Calculatethe average value of the rate constant.
Chapter 17
2.) Nitrogen dioxide decomposes according to the following reaction.
2 NO2(g) 2 NO (g) + O2 (g) Kp = 4.48 × 10−13
If 0.75 atm of NO2 is added to a container and allowed to come to equilibrium, what are the equilibrium pressures of NO and O2?
3.) Sodium bicarbonate undergoes thermal decomposition according to the reaction
2NaHCO3(s) ⇌ Na2CO3(s) + CO2(g) + H2O(g)
How does the equilibrium position shift as a result of each of the following disturbances?
a. 0.20 atm of argon gas is added.
b. NaHCO3 is added.
c. Mg(ClO4)2 is added as a drying agent to remove H2O.
d. Dry ice is added at constant T.
Chapter 18
4.) Acetic acid has a Ka of 1.8 x 10-5, and ammonia has a Kb of 1.8 x 10-5.
Find [H3O+], [OH-], pH, and pOH for:
a. 0.240 M acetic acid.
b. 0.240 M ammonia.
Chapter 19
5.) What are the [H3O+] and pH of a benzoic acid-benzoate buffer that consist of 0.33 M C6H5COOH and 0.28 M C6H5COONa? (Ka of benzoic acid = 6.3 x 10-5)
6.) A buffer that contains 0.110 M weak acid HY and 0.220 M weak base Y- has a pH of 8.77. What is the pH after 0.0020 moles of NaOH are added to 0.500 L of this buffer?