Download Fall Final Practice Test FallFinalPTest_2

A.P. Chemistry
Practice Final
Stoichiometry
1. Phenol is a compound which contains 76.57 % carbon, 6.43 % hydrogen, and 17.0%
oxygen. The empirical formula of phenol is..
a. CHO
b. CH2O
c. C3H3O
d. C2HO
e. C6H6O
2. The chemical process of rusting is described by the following equation:
4 Fe + 3 O2 ---> 2 Fe2O3
The maximum amount of rust that can be produced from 56 g of Fe and 32 g of O2 is.
a. 160 g
b. 80.g
c. 40.g
d. 120.g
e. 110.g
3. A mixture of 2.0 grams of hydrogen and 32 grams of oxygen is exploded and produces
water. What mass of gas remains uncombined?
a. 1.0 g H2
b. 8.0 g O2
c. 1.0 g O2
d. 16 g O2
e. 24 g O2
4. How many milliliters of 0.02 M HC1 are required to exactly neutralize 100 ml of 0.01 M
NaOH?
a. 50 ml.
b. 100 ml.
c. 200 ml.
d. 300 ml.
e. 400 ml.
5. What is the percentage yield for the reaction in #2 if 65 grams of rust was collected after
the reaction?
a. 80 %
b. 49 %
c. 81%
d. 86%
e. 24%
Reactions
6. The formula that shows chlorine with a oxidation number of +7 is
a. HCl
b. HClO2
c. HClO3
d. HC1O4
e. Cl2
7. Indium reacts with chlorine to form InCl3. In the balanced equation for this reaction, the
coefficient of the indium III chloride is:
a. 1
b. 2
c. 3
d. 4
e. 6
–
2+
+
8. ...Mg(s)+ ...NO3 (aq) + ...H+(aq) ...Mg (aq) +...NH4 (aq) + ...H2O(l)
When the redox equation above is balanced and all coefficients reduced to their lowest
whole-number terms, what is the coefficient for H+?
a. 4
b. 6
c. 8
d. 9
e. 10
9. Aqueous solutions of sodium sulfide and copper (II) chloride are mixed together. Which
statement is correct?
a. Both NaCl and CuS precipitate from solution
b. No precipitate forms
c. CuS will precipitate from solution
d. NaCl will precipitate from solution
e. No reaction will occur
10. Which pair of ions would not be expected to form a precipitate when dilute solutions of
each are mixed?
a. Al3+, S2b. Pb2+, Clc. Ba2+, PO43- d. Pb2+, OHe. Mg2+, SO4211. The net ionic equation for the reaction that occurs during the titration of nitrous acid with
sodium hydroxide is
a. HNO2 + Na+ + OH–  NaNO2 + H2O
b. HNO2 + NaOH  Na+ + NO2– + H2O
c. H+ + OH– H2O d. HNO2 + H2O NO2– + H3O+ e. HNO2 + OH–  NO2– + H2O
Gases, Liquids, Solids
12. Which gas occupies the largest volume?
a. Gas A: 2 moles at 760 mm and 546 K
b. Gas C: 1 mole at 380 mm and 273 K
c. Gas B: 1 mole at 760 mm and 273 K
d. Gas D: 2 moles at 760 mm and 273 K
13. Which gas contains molecules with the highest average kinetic energy?
a. Gas A: 2 moles at 273 K
b. Gas C: 1 mole at 500 K
c. Gas B: 1 mole at 293 K
d. Gas D: 2 moles at 546 K
14. The temperature at which the vapor pressure of a liquid equals the existing atmospheric
pressure at the surface of the liquid is called the
a. boiling point of the liquid.
b. equilibrium vapor pressure temperature.
c. saturation point of the atmosphere.
d. normal atmospheric temperature.
15. The assumption of the kinetic theory that explains why the pressure exerted by an
enclosed gas is constant is that
a. gases are composed of tiny invisible particles.
b. the particles of a gas are in continuous rapid motion.
c. molecules of a gas display no attraction or repulsion.
d. collisions between molecules of a gas are perfectly elastic.
16. The diffusion rate of hydrogen, H2, is 1600 meters/sec. Under similar conditions, what is
the diffusion rate of oxygen, O2 ?
a. 19.89 m/sec. b. 100.0 m/sec
c.400 m/sec. d. 6400 m/sec. e. 2.56 x 106 m/sec.
17. What is the volume taken up by 56.0 grams of nitrogen at 230C and 800 mm pressure?
a. 18.4 liters
b. 33.7 liters
c. 58.5 liters
d. 146.1 liters
e. 46.2 liters
18. A gaseous mixture containing 7.0 moles of nitrogen, 2.5 moles of oxygen, and 0.50 mole
of helium exerts a total pressure of 0.90 atmospheres. What is the partial pressure of the
nitrogen?
a. 0.13 atm
b. 0.27 atm
c. 0.63 atm
d. 0.90 atm
e. 6.3 atm
Thermochemistry
19. Given the reaction: 2 Al(s) + 3/2 O2(g)  A12O3(s); H = -1673.6 kJ/mole.
How much heat will be given off by the reaction of 27 grams of aluminum?
a. 418.4 kJ
b. 836.8 kJ
c. 1255.2 kJ d. 1673.6 kJ e. 2510 kJ
20. 3C2H2(g)  C6H6(g)
What is the standard enthalpy change, ΔH° , for the reaction represented above?
(ΔH°f of C2H2(g) is 230 kJ mol−1 ; ΔH°f of C6H6(g) is 83 kJ mol−1)
a. −147 kJ
b. −607 kJ
c. −19 kJ
d. + 19 kJ
e. +773 kJ
21. Which of the following reactions has the largest positive value of ∆S per mole of Cl2?
a. H2 (g) + Cl2 (g)  2 HCl(g)
b. Cl2 (g) + 1/2 O2 (g)  Cl2O(g)
c. Mg(s) + Cl2 (g)  MgCl2 (s) d. 2 NH4Cl(s)  N2 (g) + 4 H2 (g) + Cl2 (g)
e. Cl2 (g)  2 Cl(g)
22. How much heat is released when 75 g of octane is burned completely if the enthalpy of
combustion is -5,500 kJ/mol C8H18?
C8H18 + 25/2 O2 → 8CO2 + 9H2O
a. 7200 kJ
b. 8360 kJ
c. 4.1 × 105 kJ
d. 3600 kJ
e. 5500 kJ
23. Given the following at 25°C and 1.00 atm:
∆H0
1/2N2(g) + O2(g) → NO2(g) 33.2 kJ
N2(g) + 2O2(g) → N2O4(g) 11.1 kJ
Calculate the ∆H0 for the reaction below at 25°C.
2NO2(g) → N2O4(g)
a. +11.0 kJ
b. +44.3 kJ
c. +55.3 kJ
d. -22.1 kJ
e. -55.3 kJ
24. For a certain process at 127°C, ∆G = -16.20 kJ and ∆H = -17.0 kJ. What is the entropy
change for this process at this temperature?
a. -6.3 J/K
b. +6.3 J/K
c. -2.0 J/K
d. +2.0 J/K
e. -8.1 J/K
0
25. For the reaction given below, ∆H = -1516 kJ at 25°C and ∆S0= - 432.8 J/K at 25°C. This
reaction is spontaneous __________.
SiH4(g) + 2O2(g) → SiO2(s) + 2H2O(l)
a. only below a certain temperature
b. only above a certain temperature
c. at all temperatures
d. at no temperatures
e. cannot tell from the information available
26. The temperature of a 15-g sample of lead metal increases from 22°C to 37°C upon the
addition of 29.0 J of heat. The specific heat capacity of the lead is __________ J/g-K.
a. 7.8
b. 0.13
c. 29
d. 1.9
e. -29
Atomic Theory
27. The elements in which of the following have most nearly the same atomic radius?
a. Be, B, C, N
b. C, P, Se, I c. Ne, Ar, Kr, Xe d. Cr, Mn, Fe, Co e. Mg, Ca, Sr, Ba
Use these answers for questions 28-30.
a. O b. La
c. Rb
d. Mg e. N
28. What is the most electronegative element of the above?
29. Which element exhibits the greatest number of different oxidation states?
30. Which of the elements above has the smallest ionic radius for its most commonly found
ion?
Bonding
31. Which of the following has a zero dipole moment?
a. HCN
b. SO2
c. PF5
d. NH3
e. NO2
Questions 32-33
a. A network solid with covalent bonding
b. A molecular solid with zero dipole moment
c. A molecular solid with hydrogen bonding
d. An ionic solid
e. A metallic solid
32. Solid ethyl alcohol, C2H5OH
33. Silicon dioxide, SiO2
34. Which of the following molecules has the shortest bond length?
a. Br2
b. Cl2
c. I2
d. O2
e. N2
35. Pi (π) bonding occurs in each of the following species EXCEPT
a. CO2
b. CH4
c. CN–
d. C2H4
e. C6H6
Questions 36-39. Give the types of intermolecular forces in the following substances:
36. Cl2
37. H2O
38. NH3
39. Ne
a. LDF b. dipole-dipole
c. hydrogen bonding
d. ionic
e. covalent
40. In which of the following groups of substances would dispersion forces be the only
significant factors in determining boiling point?
1. Cl2
2. HF
3. Ne
4. KNO2
5. CCl4
a. 2, 5
b. 1, 2, 3
c. 2, 4
d. 1, 3, 5
e. 3, 4, 5
41. In the BeF2 molecule the Be valence orbitals are:
a. sp hybridized
b. sp2 hybridized
c. sp3 hybridized
d. dsp2 hybridized
2
2
42. Which of the following molecules contains an sp -sp sigma bond?
a. CH4
b. C2H2
c. C2H4
d. C2H6
e. none of these
Questions 43-44: Choose the correct shape:
a. linear
b. trigonal planar
c. tetrahedral
43. NO3
44. ClF2+
d. bent
e trigonal pyrimdal
Solutions
45. How many grams of solute are contained in 141 mL of a 0.175 M silver nitrate solution?
a. 6.85 g
b. 3.80 g
c. 0.145g
d. 4.19g
e. 0.175
46. What is the mole fraction of ethanol, C2H5OH, in an aqueous solution in which the
ethanol concentration is 4.6 molal?
a. 0.0046
b. 0.083
c. 0.72
d. 0.20
e. 0.076
47. Addition of a nonvolatile solute to a solvent
a. lowers the freezing point and the boiling point.
b. raises the freezing point and the boiling point.
c. lowers the freezing point and raises the boiling point.
d. raises the freezing point and lowers the boiling point.
e. only affects the freezing point.
48. Which of the following has the least effect on the Solubility of a solid in a liquid solvent?
a. temperature
b. nature of the solvent
c. nature of the solute
d. pressure
e. structure of the molecules
49. How many milliliters of 11.6-molar HCl must be diluted to obtain 1.0 liter of 3.0-molar
HCl?
a. 3.9 mL
b. 35 mL
c. 260 mL
d. 1,000 mL
e. 3,900 mL
50. When 34.5 grams of a non-volatile non-electrolyte are dissolved in 1000 grams of water,
the freezing point of the resulting solution is -0.770C. What is the molar mass of the
solute? (Kfp = -1.86 deg/molal)
a. 83
b. 97
c. 124
d. 162
e. 205
ANSWERS
1. E
2. B
3. D
4. A
5. C
6. D
7. B
8. E
9. C
10. E
11. E
12. A
13. D
14. A
15. B
16. C
17. E
18. C
19. B
20. B
21. D
22. D
23. E
24. C
25. A
26. B
27. D
28. A
29. B
30. D
31. C
32. C
33. A
34. E
35. B
36. A
37. B & C
38. B & C
39. A
40. D
41. A
42. C
43. B
44. D
45. D
46. E
47. C
48. D
49. C
50. A