Download Chemistry Midterm Exam for Course 142A: Solutions and Equilibria and Gases and more Exams Chemistry in PDF only on Docsity! Name (please print)_________________________________ Signature_________________________________________ TA Name/Quiz Section______________________________ CHEMISTRY 142A Oleg Prezhdo Midterm Two (Closed Book) Tuesday, November 29, 2005 15 problem, equal weight. Not-multiple choice problems receive partial credit where applicable. NOTES: (a) Before starting check to make sure the exam has all the 7 pages, plus a list of constants and equations and a copy of the periodic table. (b) Print name and sign the first page. Print your name at the top of each page. This will allow us to put your exam back together if the staple comes loose. (c) The exam is over promptly at 9:20 AM. No work is allowed after that time. (d) If you need more room, do your work on the back of the page, and make sure to indicate this. Name_______________________________ 2 Chemical Equilibrium, Chapter 6. Problem 1. Problem 2. Problem 3. Name_______________________________ 5 Problem 9. Problem 10. Problem 11. Problem 12. Name
Problem 13.
70. Which statement about kinetic energy (K_E_) is true?
a) All objects moving with the same velocity have the same KE
b) As the velocity of a body increases, its KE. decreases
c) The KE. ofa body will double it its velocity doubles:
d) The KE. of a body is independent of its mass.
e) none of these
ANS: e) none of these PAGE: 5.6
Problem 14.
63. A gaseous mixture containing 1.5 mol Ar and 3.5 mol CO, has a total pressure of 7.0
atm. What is the partial pressure of CO,?
a) 13atm
b) 21atm
ce) 3.5atm
d) 49atm
e) 24atm
ANS: d) 49atm PAGE: 5.5.
Problem 15.
46. Into a 3.00-liter container at 25°C are placed 1.23 moles of O, gas and 3.20 moles of solid
C (graphite). If the carbon and oxygen react completely to form CO(g), what will be the
final pressure in the container at 25°C?
a) 20.1 atm
b) 261atm
c) 10.2atm
d) 1.68 atm
e) none of these
ANS: a) 20.latm PAGE: 5.4
Name_______________________________ 7 CONSTANTS Avogadro’s number: NA = 6.022 x 1023 mol-1 The charge of an electron: e = -1.602 x 10-19 C The mass of an electron: me = 9.109 x 10-31 kg The mass of a proton: mp = 1.672 x 10-27 kg The mass of a neutron: mn = 1.675 x 10-27 kg Universal gas constant: R = 0.082 atm L mol-1 K-1 = 8.314 J mol-1 K-1 EQUATIONS Ideal gas law: PV = nRT The kinetic theory of gases: urms = (3RT/M)1/2; ump = (2RT/M)1/2; uavg = (8RT/ M)1/2 Density = mass/volume 1 atm = 760 mmHg = 760 torr = 1.013 x 105 Pa J = kg m2 s-2
