108-3rd Chem Exam (B)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) The pressure exerted by a column of liquid is equal to the product of the height of the column times the gravitational constant times the density of the liquid, P = ghd. How high a column of water (d = 1.0 g/mL) would be supported by a pressure that supports a 713 mm column of mercury (d = 13.6 g/mL)?
A) 1.2 × 104 mm B) 14 mm C) 713 mm D) 9.7 × 103 mm
E) 52 mm Answer: D
2) Standard temperature and pressure (STP), in the context of gases, refers to __________.
A) 273.15 K and 1 torr B) 298.15 K and 1 atm C) 273.15 K and 1 atm D) 298.15 K and 1 torr
E) 273.15 K and 1 pascal Answer: C
3) The reaction of 50 mL of Cl2 gas with 50 mL of C2H4 gas via the equation:
Cl2 (g) + C2H4 (g) C2H4Cl2 (g)
will produce a total of __________ mL of products if pressure and temperature are kept constant.
A) 25 B) 50 C) 100 D) 150 E) 125
Answer: B
4) Of the following gases, __________ will have the greatest rate of effusion at a given temperature.
A) HCl B) Ar C)NH3 D)CH4 E) HBr
Answer: D
5) The volume of an ideal gas is zero at __________.
A) -363 K B) -273 K C) -45 °F D) 0 °C E) -273 °C
Answer: E
6) Which one of the following gases would deviate the least from ideal gas behavior?
A)CH3Cl B) Kr C) Ne D)F2 E)CO2
Answer: C
7) The volume of a sample of gas (2.49 g) was 752 mL at 1.98 atm and 62 °C. The gas is __________.
A) Ne B)SO3 C)NO2 D)NH3 E)SO2
Answer: C
8)The density of NO2 in a 4.50 L tank at 760.0 torr and 25.0 °C is __________ g/L.
A) 1.64 B) 9.30 C) 3.27 D) 1.88 E) 1.68
Answer: D
9) Which noble gas is expected to show the largest deviations from the ideal gas behavior?
A) argon B) neon C) krypton D) helium E) xenon
Answer: E
10) The basis of the VSEPR model of molecular bonding is __________.
A) atomic orbitals of the bonding atoms must overlap for a bond to form
B) hybrid orbitals will form as necessary to, as closely as possible, achieve spherical symmetry
C) electron domains in the valence shell of an atom will arrange themselves so as to minimize repulsions D) regions of electron density on an atom will organize themselves so as to maximize s-character
E) regions of electron density in the valence shell of an atom will arrange themselves so as to maximize overlap
Answer: C
11) The bond angles marked a, b, and c in the molecule below are about __________, __________, and __________, respectively.
A) 90°, 90°, 90°
B) 109.5°, 120°, 109.5°
C) 120°, 120°, 109.5°
D) 109.5°, 90°, 120°
E) 120°, 120°, 90°
Answer: B
12)The molecular geometry of the SF6 molecule is __________, and this molecule is __________.
A) trigonal planar, polar B) octahedral, nonpolar C) trigonal bipyramidal, polar D) trigonal planar, nonpolar
E) trigonal pyramidal, polar Answer: B
13) The hybridization of the oxygen atom labeled y in the structure below is __________. The C-O-H bond angle is __________.
A) sp3d2, 90° B) sp3, 109.5° C) sp, 180° D) sp, 90° E) sp2, 109.5°
Answer: B
14)There are __________ bonds and __________ bonds in H3C-CH2-CH CH-CH2-C CH.
A) 10, 3 B) 12, 2 C) 13, 2 D) 16, 3 E) 14, 2
Answer: D
15) Based on molecular orbital theory, there are __________ unpaired electrons in the OF+ ion.
A) 0 B) 3 C) 2 D) 1 E) 1/2
16)ClF3 has "T-shaped" geometry. There are __________ non-bonding domains in this molecule.
A) 3 B) 0 C) 4 D) 2 E) 1
Answer: D
17) The electron domain and molecular geometry of BrO2- is __________.
A) trigonal pyramidal, linear B) trigonal planar, trigonal planar C) tetrahedral, trigonal planar D) tetrahedral, bent
E) trigonal pyramidal, seesaw Answer: D
18) The molecular geometry of the right-most carbon in the molecule below is __________.
A) tetrahedral B) octahedral
C) trigonal bipyramidal D) trigonal planar
E) T-shaped Answer: D
19) Based on molecular orbital theory, the bond orders of the H H bonds in H2, H2+, and H2- are __________, respectively
A) 1, 0, and 0 B) 1, 1/2, and 1/2 C) 1, 2, and 0 D) 1, 0, and 1/2
E) 1, 1/2, and 0 Answer: B
20)Based on molecular orbital theory, the bond order of the N N bond in the N2 molecule is __________.
A) 0 B) 1 C) 2 D) 3 E) 5
Answer: D
21) Based on molecular orbital theory, the bond order of the N N bond in the N22+ ion is __________.
A) 1/2 B) 2 C) 3 D) 0 E) 1
Answer: B
22) Of the following, __________ appear(s) to gain mass in a magnetic field.
B2 N2 O2
A)N2 only B)B2 and O2 C)O2 only D)N2 and O2 E)B2 and N2
Answer: B
23) Which of the following is not a type of solid?
A) supercritical B) molecular C) metallic D) ionic
E) covalent-network Answer: A
24) The scattering of light waves upon passing through a narrow slit is called __________.
A) diffusion B) adhesion C) incidence D) grating E) diffraction
Answer: E
25) Inorganic compounds that are semiconductors have an average of __________ valence electrons.
A) 5 B) 4 C) 2 D) 3 E) 1
Answer: B
26) The process of doping can produce a __________ which can greatly __________ intrinsic conductivity.
A) non-metal, increase
B) p-type semiconductor, decrease C) non-metal, decrease
D) n-type semiconductor, increase E) allotrope, diminish
Answer: D
27) The formation of a condensation polymer generally involves __________.
A) the mixing of sulfur with an addition polymer B) the elimination of a small molecule
C) the formation of significant crosslinking D) the vaporization of a plasticizer
E) the addition of a plasticizer Answer: B
28) What fraction of the volume of each corner atom is actually within the volume of a face-centered cubic unit cell?
A) 1 B) 1/2 C) 1/4 D) 1/8 E) 1/16
Answer: D
29) If the electronic structure of a solid substance consists of a valence band that is completely filled with electrons and there is a large energy gap to the next set of orbitals, then this substance will be a(n) __________.
A) conductor B) nonmetal C) semiconductor D) insulator
E) alloy Answer: D
30) NaCl crystallizes in a face-centered cubic cell. What is the total number of ions (Na+ ions and Cl- ions) that lie within a unit cell of NaCl?
A) 4 B) 5 C) 8 D) 2 E) 6
Answer: C
31) Which of the following is not classified as a nanomaterial?
A) buckminsterfullerene B) isoprene
C) graphene
D) carbon nanotubes
E) All of the above are classified as nanomaterials Answer: B
32) Of the following, __________ has the highest boiling point.
A)O2 B)Br2 C)H2 D)N2 E)Cl2
Answer: B
33) In which of the following molecules is hydrogen bonding likely to be the most significant component of the total intermolecular forces?
A)C6H13NH2 B)CH3OH C)CH4 D)C5H11OH E)CO2
Answer: B
34)What types of intermolecular forces exist between HI and H2S?
A) dispersion forces, dipole-dipole, and ion-dipole B) dispersion forces, dipole-dipole, and ion-dipole C) dipole-dipole and ion-dipole
D) dispersion forces and dipole-dipole
E) dispersion forces, hydrogen bonding, dipole-dipole, and ion-dipole Answer: D
35) Which statements about viscosity are true?
(i) Viscosity increases as temperature decreases.
(ii) Viscosity increases as molecular weight increases.
(iii) Viscosity increases as intermolecular forces increase.
A) (i) only B) (i) and (iii) C) (ii) and (iii) D) none E) all Answer: E
36) Based on the following information, which compound has the strongest intermolecular forces?
Substance Hvap (kJ/mol)
Argon (Ar) 6.3
Benzene (C6H6) 31.0
Ethanol (C2H5OH) 39.3
Water (H2O) 40.8
Methane (CH4) 9.2
A) Argon B) Ethanol C) Methane D) Benzene E) Water
Answer: E
37) The strongest interparticle attractions exist between particles of a __________ and the weakest interparticle attractions exist between particles of a __________.
A) solid, liquid B) liquid, gas C) liquid, solid D) gas, solid E) solid, gas Answer: E
38) Which one of the following exhibits dipole-dipole attraction between molecules?
A)CCl4 B)Br2 C)CO2 D)PH3 E)C10H22
Answer: D
39) The slope of a plot of the natural log of the vapor pressure of a substance versus 1/T is __________.
A) - Hvap
R B) 1
Hvap C) - Hvap D) Hvap E) -1
Hvap Answer: A
40) Which of the following is most likely to exhibit liquid-crystalline behavior?
A) CH3CH2CH2CH2CH2- Na+
B)
C)CH3CH2CH2CH2CH2CH2CH2CH3 D)
E)CH3CH2-C(CH3)2-CH2CH3 Answer: D
