CHEM 102 – Winter 18 Final Exam Review Practice Problems
1) What is the name of the compound
... [Show More] below?
A) 2-ethyl-2-butene
B) 2-ethylbutane
C) 3-methyl-2-pentene
D) 3-methyl-3-pentene
E) 2,2-ethyl-2-butene
2) Proteins are biopolymers formed via multiple condensation coupling of which two monomers?
A) ester and diamine
B) diamine and dicarboxylic acid
C) dialcohol and amide
D) dialcohol and diamine
E) alcohol and carboxylic acid
3) Which of the following substances would exhibit dipole-dipole intermolecular forces?
A) BCl3
B) CF4
C) CO2
D) Cl2
E) NH3
4) Which of the following would have the lowest vapor pressure at 0°C?
A) CH4
B) CH2Cl2
C) NH3
D) CH3OCH3
E) CH3COOH
5) In going from point A to B to C, what processes does CO2 undergo?
A) exothermic; exothermic
B) exothermic; endothermic
C) endothermic; endothermic
D) endothermic; exothermic
E) endothermic; isothermal
6) What is the length of time required for the following first-order reaction to have used up all but 25% of the starting material?
2H2 + C2H2 C2H6 k = 0.277 min-1
A) 0.6 min
B) 2.5 min
C) 100 min
D) 5.0 min
E) 7.5 min
7) Which of the following statements concerning catalysts is incorrect?
A) Catalysts affect the reaction rate, but do not appear in the rate law.
B) Catalysts are formed in one step of a reaction mechanism and consumed in another.
C) Catalysts lower the activation energy for the reaction.
D) Catalysts usually change the mechanism for a reaction.
E) Catalysts may be insoluble in the reaction solvent.
8) At equilibrium in the following reaction at 319 K, the partial pressure of NO2 (g) is 2.09 atm. What is the partial pressure of N2O4 (g) if the equilibrium constant for this reaction is determined to be 39.68 at 319 K?
2 NO2 (g) ⮀ N2O4 (g)
A) 173 atm
B) 362 atm
C) 82.9 atm
D) 19.0 atm
E) 0.110 atm
9) The value of Keq for the equilibrium H2 (g) + I2 (g) ⮀ 2 HI (g)
is 794 at 25 °C. At this temperature, what is the value of Keq for the equilibrium below?
HI (g) ⮀ 1/2 H2 (g) + 1/2 I2 (g) A) 1588
B) 28
C) 397
D) 0.035
E) 0.0013
10) Which change will increase the quantity of product in the following reaction? C2H4 (g) + Cl2 (g) ⮀ C2H4Cl2 (g) ΔH° = -174 kJ
A) an increase in temperature
B) a decrease in volume of container
C) a decrease in pressure
D) adding a catalyst
E) increasing pressure by adding some argon
11) Which direction will the following reaction (in a 5.0 L flask) proceed if the pressure of CO2(g) is 1.0 atm?
CaCO3 (s) ⮀ CaO (s) + CO2 (g) Kp = 1.9 × 10−23
A) to the right because Q > Kp
B) to the left because Q > Kp
C) to the right because Q < Kp
D) to the left because Q < Kp
E) The reaction is at equilibrium.
12) A saturated solution .
A) contains as much solvent as it can hold
B) contains no double bonds
C) contains dissolved solute in equilibrium with undissolved solid
D) will rapidly precipitate if a seed crystal is added
E) cannot be attained
13) What is the pOH of an aqueous solution if [HCl] = 0.00060 M? A) 10.78
B) 7.56
C) −17.22
D) 3.78
E) 12.39
14) The pH of a 0.10 M solution of hydrazoic acid, HN3, is 2.86. Calculate the Ka value for hydrazoic acid.
A) 1.9 × 10−6
B) 1.4 × 10−4
C) 2.0 × 10−5
D) 1.4 × 10−3
E) 2.6 × 10−8
15) Which combinations will serve as buffers when equal volumes of 0.20 M solutions are mixed?
I) HCl/KCl II) HF/NaF III) NaH2PO4/Na2HPO4 IV) HNO3/NaOH
A) I and II
B) I and IV
C) II and III
D) III and IV
E) I and III
16) Calculate the molar solubility of Al(OH)3. (Ksp = 1.3 × 10−33) A) 1.8 × 10−17 M
B) 4.8 × 10−35 M
C) 6.0 × 10−9 M
D) 1.3 × 10−33 M
E) 2.6 × 10−9 M
17) What will be the effect of adding 0.10 mol Ca2+ to the following reaction at equilibrium?
CaC2O4 (s) ⮀ Ca2+ (aq) + C O 2− (aq)
2 4
A) [Ca2+] will decrease.
B) [C O 2-] will increase.
2 4
C) Solubility will decrease.
D) Ksp will increase.
E) There will be no change to the system.
18) Which of the following statements is incorrect?
A) The more atoms in its molecules, the greater will be the entropy of a substance.
B) If a process is spontaneous, the reverse process is nonspontaneous.
C) The greater the degree of disorder in a system, the more negative is its entropy.
D) The entropy of a pure, perfect crystal is zero at 0 K.
E) The entropy of the universe must always increase for a spontaneous process.
19) Calculate ΔG° for the following reaction at 25°C. ΔGf° (NH3) = -16.48 kJ/mol. 2 NH3(g) ⮀ N2(g) + 3 H2(g)
A) -16.48 kJ
B) 16.48 kJ
C) 0 kJ
D) 32.96 kJ
E) -32.96 kJ
20) The following reaction is endothermic: 3 O2(g) 2 O3(g). The reaction is
A) spontaneous at all temperatures.
B) non-spontaneous at all temperatures.
C) spontaneous at low temperatures.
D) spontaneous at high temperatures.
21) What is the equilibrium constant for a reaction whose △G° = 1.23 kJ/mol at -110°C? (R =
8.314 J/mol-K)
A) 0.404
B) 1.24 x 10–1
C) -0.908
D) 3.40 x 10–1
E) 0.00
22) Which transformation could take place at the anode of an electrochemical cell?
A) Cr2O72- Cr3+
B) F2 F -
C) O2 H2O
D) HAsO2 As
E) None of the above could take place at the anode.
23) The standard cell potential (E) for the cell using the overall cell reaction below is +0.48 V: Zn (s) + Ni2+ (aq) Zn2+ (aq) + Ni (s)
What is the cell potential generated by the cell at 25C when [Ni2+] = 2.50 M and [Zn2+] = 0.100 M?
A) 0.40 V
B) 0.50 V
C) 0.52 V
D) 0.56 V
E) 0.44 V
24) Write the net equation for the redox reaction that occurs in the following voltaic cell.
Cu(s) / Cu2+(aq) // Ag+(aq) / Ag(s)
A) Cu(s) + 2 Ag+(aq) Cu2+(aq) + 2 Ag(s)
B) Cu(s) + Cu2+(aq) 2 Ag+(aq) + Ag(s)
C) Cu2+(aq) + 2 Ag(s) Cu(s) + 2 Ag+(aq)
D) 2 Ag+(aq) + Ag(s) Cu(s) + Cu2+(aq)
E) Cu(s) + Ag+(aq) Cu2+(aq) + Ag(s)
Answers:
1) C
2) B
3) E
4) E
5) D
6) D
7) B
8) A
9) D
10) B
11) B
12) C
13) A
14) C
15) C
16) E
17) C
18) C
19) D
20) B
21) A
22) E
23) C
24) A [Show Less]