Chem 1210, Final Exam, Fall 2001
Final Exam
Chemistry 1210
Fall 2001
Prof. Lance Seefeldt
December 12, 2001
You may begin the exam at 7:00 AM. You have until 8:50 AM.
This exam should have 50 questions. Each question is worth 4 points for a total of 200 points.
Use only a #2 Pencil to mark the best answer on the Scantron sheet. You will turn in only the Scantron sheet. You should keep the rest of the exam.
On the Scantron sheet, fill in your last name, first and middle initials, identification number (this is your social security number). Also fill in the appropriate bubbles.
Your score on the exam will be sent to your University email address. The answer key will be posted on the course web page at
Good luck and have a great Holiday!
Information:
Density = mass/volumeF = (9/5)(C) + 32C = 5/9 (F – 32)
K = C + 2731 inch = 2.54 cmAvogardo’s number = 6.02 x 1023
1 kg = 2.205 lbsh = 6.63 x 10-34 J sc = 3.0 x 108 m/s
RH = 2.18 x 10-18 J1 J = 1 kg m2/s2 = c = h/mv
E = hH = Hfinal - Hinitial HRxt = (nHproducts) – (mHreactants)
Specific heat = q/m TSpecific heat water = 4.18 J/g K
Zeff = Z – S En = -RH (1/n2)E = RH (1/ni2 – 1/nf2)
Lattice Energy = kQ1Q2/dH = (bonds broken)- (bonds formed)
PV = nRTP1V1/T1 = P2V2/T21 atm=101 kPa=760 torr=760 mm Hg
R = 0.0821 L*Atm/mol*KPA = XAPA
Tf = KfmTb = Kbm = MRT
Chapters 11 and 13
1) Which of the following substances would exhibit hydrogen bonding in the liquid state?
a) PH3b) H2Sc) CH4d) NH3
2) Which of the following characteristics indicates the presence of weak intermolecular forces in a liquid
a)A low heat of vaporization
b)A high critical temperature
c)A low vapor pressure
d)A high boiling point
3) Which of the following substances would have the highest boiling point?
a)CH4
b)Cl2
c)Kr
d)CH3Cl
4) Each of the following substances is a gas at 25C and 1 atm pressure. Which one will liquefy most easily when compressed at a constant temperature?
a)F2
b)Ar
c)H2
d) HF
5) A liquid boils when its?
(a)Vapor pressure is exactly 1 atm
(b)Vapor pressure is equal to, or greater than, the external pressure
(c)Temperature is equal to 273 K
(d)Temperature is greater than room temperature
6) Use the graph of vapor pressure to determine the normal boiling point of CHCl3.
a)64C
b)19C
c)70C
d)52C
7) Freon-11 (CCl3F) has a boiling point of 23.8C and specific heat capacities for the liquid phase of 0.87 J/g-K and for the gas phase of 0.59 J/g-K. The enthalpy of vaporization is 24.75 kJ/mol. What is the enthalpy change for conversion of Freon-11 from –50C to 50C?
a)2.61 kJ
b)100 J
c)56 J
d)6.0 kJ
8) Which of the following is not an endothermic process?
a)Melting of a solid
b)vaporization
c)sublimation of dry ice
d)condensation of water vapor
9) The figure shows how the temperature of a substance changes as heat is added. Which term describes the process going from A to B?
a)freezing
b)sublimation
c)melting
d)condensation
10) Which of the following classes of solids would you predict to be the hardest
a)molecular solids
b)covalent solids
c)ionic solids
d)metallic solids
11) Increasing the pressure from 1 atm to 1.5 atm on ice at –2.0C results in
a)no change in state
b)the conversion to the liquid state
c)the conversion to the gas state
d)none of the above
12) On the phase diagram for CO2, which is the critical point
a)A
b)B
c)C
d)D
13) Which of the following combinations does not make a homogeneous solution
Choice / Solute / SolventA / Gas / Gas
B / Solid / Gas
C / Solid / Liquid
D / Liquid / Solid
14) For the addition of NaCl to water, which of the following processes will be exothermic
a)NaCl going to Na+ and Cl-
b)Breaking intermolecular interactions between water molecules
c)Solvation of the Na+ and Cl-
d) Breaking the NaCl ionic interactions
15) The arsenic concentration in a water supply is reported to be 0.090 % w/w. What is the arsenic concentration in ppm (recall that ppm = mg solute/kg solution).
a)900 ppm
b)9 ppm
c)0.9 ppm
d)0.09 ppm
16) What is the molality of a solution with 13.0 g C6H6 (FW=78 g/mol) in 17.0 g CCl4 (FW=154 g/mol)?
a)9.8
b)0.0098
c)98
d)0.98
17) The solubility of CO2(g) in water
a)increases with increasing temperature
b)decreases with decreasing temperature
c)decreases with increasing temperature
d)is not dependent on temperature
18) According to Raoult’s law, which statement is false
a)the vapor pressure of a solvent over a solution decreases as its mole fraction increases
b)the vapor pressure of a solvent over a solution is less than that of pure solvent
c)the greater the pressure of a gas over a solution, the greater its solubility
d)ionic solutes dissociate in solution causing an enhancement of colligative properties.
19) What is the freezing temperature of a solution that contains 10.0 g of glucose (C6H12O6) in 100 g of H2O. The Kf for water is 1.86C/m.
a)–0.186C
b)+0.186C
c)–1.03C
d)–0.1C
20) Which of the following aqueous solutions has the highest osmotic pressure at 25C?
a)0.2 M KBr
b)0.2 M NaCl
c)0.2 M Na2SO4
d)0.2 M KCl
21) How many grams of NaCl would have to be added to 1 L of water to raise the boiling temperature by 1.0C? (Kb is 0.52C/m)
a)2.45 g
b)112.3 g
c)56.16 g
d)32.2 g
22) What is the osmotic pressure of a 0.0020 M solution of the non-electrolyte sucrose in water at 20C?
a)0.048 atm
b)1.02 atm
c)22.4 atm
d)0.224 atm
23) Which of the following molecules would be the least soluble in CCl4?
a)H2O
b)CH4
c)I2
d)H2
24) When ammonium acetate is dissolved in water, the temperature of the solution drops. The formation of a solution can be partially attributed to?
a)The exothermic nature of the solution formation
b)The increase in disorder or entropy
c)The energy released when solute-solute interactions are disrupted
d)The energy absorbed due to solute-solvent interactions
25) There are __ mmoles in 1 mole
a)100
b)1000
c)0.01
d)0.001
Comprehensive
26) A cup of hot water is found to drop in temperature from 50F to 27F over 2 hours. What is the temperature drop expressed in Kelvin (K).
a)286 K
b)12.8 K
c)44.8 K
d)5.0 K
27) A cube is found to be 25 inches long on each edge. What is the volume of the cube in mL?
a) 1.66 x 104 mL
b) 4.03 x 103 mL
c) 25 mL
d) 2.6 x 105 mL
28) Copper (Cu) forms cations with charges of 1+ and 2+. What is the correct formula for cupric chloride
a)CuCl2
b)CuCl
c)Cu2Cl
d)Cu2Cl2
29) A solution is prepared by placing 14.5 g of NaCl into a flask and adding water to a final volume of 0.5 L. What is the concentration of NaCl in solution
a)1.0 M
b)0.25 M
c)4.0 M
d)0.5 M
30) Starting with 5.0 g of H2 and 5.0 g of O2, if the reaction below goes to completion, how many grams of H2O would result?
2 H2 + O2 2 H2O
a) 2.8 g
b)5.6 g
c)5.0 g
d)1.2 g
31) If a system has 5 J of work done on it, and liberates 3 J of heat to the surroundings, what is the energy change of the system?
a) +2 Jb) –2 Jc) +8 Jd) –8 J
32) For the reaction below, the enthalpy change is known to be –1323 kJ.
C2H4 + 3O2(g) 2CO2(g) + 2H2O(l)
Given the known enthalpies of formation
CompoundHf
CO2(g)-393.8 kJ/mol
H2O(l) -241.8 kJ/mol
What is the Hf for C2H4?
a)+51.8 kJ/mol
b)–1323 kJ/mol
c)–51.8 kJ/mol
d)+ 1323 kJ/mol
33) How many valence electrons are in the ground state of Zn
a)30
b)18
c)10
d) 12
34) Which of the following would seem a reasonable value for the electron affinity for Cl
a)0 kJ/mol
b)+50 kJ/mol
c)+300 kJ/mol
d)–300 kJ/mol
35) Which of the following energy transitions for the H atom would produce the shortest wavelength of electromagnetic radiation
a)n=4 to n=1
b)n=2 to n=1
c)n=1 to n=4
d)n=1 to n=2
36) For n = 4, how many values of l are there?
a)4
b)3
c)2
d)9
37) Rank the following from largest to smallest atomic radius
I, I-, Xe
a)I > I- > Xe
b)Xe > I > I-
c)I- > I > Xe
d)Xe > I- > I
38) Which of the following is a reasonable estimate for the H-N-H bond angle in NH3
a)120
b)107
c)109.5
d)116
39) A soda can (350 mL) at 100C has 0.0114 moles of gas at 1 atm pressure. The can is sealed and then cooled to 0C. What must the final volume of the can be if the pressure returns to 1 atm?
a)256 mL
b)140 mL
c)94 mL
d)0 mL
40) How much faster does a N2 filled balloon deflate compared to the same balloon filled with O2 (hint r1/r2 =
a)3.7 times faster
b)2.6 times faster
c)1.07 times faster
d)100 times faster
41) For a particular gas, which of the following conditions would result in the largest deviation from ideal gas behavior?
a)700 K, 500 atm
b)200 K, 400 atm
c)270 K, 760 torr
d)25C, 700 mm Hg
42) What is the concentration of a 750.0 mL solution that contains 50.0 g of Mg(NO3)2. (Molar mass Mg(NO3)2 is 148.33 g/mol).
a)4.49 x 10-4 M
b)9.89 x 10-3 M
c)0.449 M
d)9.89 M
43) What mass of Al contains the same number of atoms as 6.79 g of Zn?
a)1.87 g
b)2.80 g
c)6.79 g
d)16.5 g
44) How many neutrons and electrons are in 32P3-
a)17 n, 15 e-
b)17 n, 18 e-
c)18 n, 15 e-
d)18 n, 18 e-
45) Which represents the elements in order of increasing electronegativity?
a)As < Se < Te
b)Br < Cl < S
c)Sb < I < Br
d)Se < Br < Te
46) What is the electron pair geometry around O in H2O
a)Linear
b)Tetrahedral
c)Bent
d)Trigonal pyramidal
47) Which combination of elements will form an ionic bond
a)K and F
b)C and Cl
c)N and O
d)B and N
48) Which of the following would not have an enthalpy of formation (Hf) of zero
a)O2
b)O3
c)N2
d)He
49) Which molecule would you predict to have the lowest boiling temperature
a)He
b)Ne
c)Xe
d)Kr
50) What is a reasonable atmospheric pressure on the top of Mt. McKinley (elevation 20,320 feet)?
a)230 mm Hg
b)798 mm Hg
c)945 mm Hg
d)20,320 mm Hg
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