CHEMISTRY 1412 Practice Exam 1
Chapters 10,11 and 13
I am including chapter 10 so that you can practice the information that you need for chapter 10
1. Which type of bond is the longest?
a) single b) double c) triple d) all are the same length
2. What is the formal charge of nitrogen in the nitrate ion, NO3–?
a) 0 b) +1 c) –1 d) +2
3. The best Lewis dot structure of the NO molecule has
a) an unpaired electron on the nitrogen atom
b) an unpaired electron on the oxygen atom
c) a triple bond between N and O
d) an expanded octet on N
4. The central carbon atom in the carbonate ion, CO32-, has
a) 3 , 0 bonds b) 2 , 1 bonds
c) 3 , 1 bonds d) 3 , 2 bonds
5. The type of compound that is most likely to contain an ionic bond is
a) one that is composed of a metal and a nonmetal
b) a solid metal
c) one that is composed of only nonmetals
d) one that is nonpolar
6. Which compound has the lowest lattice energy?
a) NaCl b) NaBr c) MgCl2 d) MgBr2
7. The lattice energy of an ionic solid is greater if
a) the ions have large sizes
b) the charges of the ions are high
c) the distance between the ions is large
d) the distance between the ions is large and the charges are low
8. Which molecule is polar?
a) CS2 b) PCl3 c) BCl3 d) SCl6
9. The PO43–ion has how many total valence electrons?
a)24 b) 30 c) 32 d) 34 e) 36
10. Of the molecules below, which is the most polar?
a) HBr b) HF c) HCl d) HI
11. Given the electronegativities below, which of the following covalent
single bonds is the least polar?
Element: H C N O
Electronegativity: 2.1 2.5 3.1 3.5
a)O-H b) N-H c) C-H d) O-C e) C-N
12. What is the formal charge of the carbon atom in the carbon monoxide
molecule?
a a) 0 b) +1 c) –1 d) +2 e) –2
13. The Lewis electron-dot structure of PF3 gives the central P atom
a) 2 nonbonding pairs and 2 bonding pairs of electrons
b) 1 nonbonding pair and 3 bonding pairs of electrons
c) 3 nonbonding pairs and 1 bonding pair of electrons
d) 2 nonbonding pairs and 3 bonding pairs of electrons
14. Draw the correct Lewis electron-dot formula of CO32–?
15. How many resonance forms can be drawn for the NO3– ion?
a) 0 b) 1 c) 2 d) 3
16. Which of these violates the octet rule?
a) SF4 b) PCl3 c) SiF4 d) CS2
17. In the trigonal bipyramidal geometry, lone electron pairs occupy the
a) axial positions b) equatorial positions
18. The overall geometry and molecular geometry of bromine trifluoride, BrF3, are, respectively
a) trigonal planar, trigonal planar
b) tetrahedral, trigonal pyramidal
c) trigonal bipyramidal, T-shaped
d) octahedral, square planar
19. Predict the overall geometry about the carbon atoms in the molecule
acetaldehyde shown below:
a) square planar, trigonal planar
b) bent, tetrahedral
c) tetrahedral, trigonal pyramidal
d) tetrahedral, trigonal planar
20. What is the molecular geometry of an NH3 molecule?
a) linear b) bent
c) trigonal pyramidal d) tetrahedral
21. Which one of the following molecules would be expected to have bond
angles of 120?
a) SO3 b) ClO3 c) NCl3 d) BCl4
22. Which one of the following molecules is paramagnetic?
a) N2 b) B2 c) F2 d) C2
23. What type of intermolecular force occurs between water molecules?
a) ion-dipole b) dipole-dipole c) London dispersion d) covalent
24. What type of intermolecular force would be important when KBr dissolves
in water?
a) ion-dipole b) dipole-dipole c) London dispersion d) covalent
25. Which molecule exhibits hydrogen bonding interactions with water?
a) CCl4 b) CH3OH c) CBr4 d) Ar
26. Viscosity is
a) The energy required to expand the surface of a liquid.
b) The attraction between molecules.
c) The resistance to flow of a liquid.
d) The energy required to melt a solid.
27. The attraction between water molecules and a glass surface is an
example of
a) adhesion
b) cohesion
c) viscosity
d) surface tension
28. The conversion of a solid to a gas is called
a) melting
b) vaporization
c) condensation
d) sublimation
29. How much heat is required to convert 50.0 g of ice at 0°C to water
vapor at 100°C? The heat of fusion of water is 334 J/g, the heat of
vaporization of water is 2264 J/g, and the specific heat of water is
4.184 J/g°C.
a) 78.45 kJ b) 150.82 kJ c) 234.15 kJ d) 316.23 kJ
30. What is the molarity of a solution prepared by dissolving 10.0 g of KNO3 in 250 mL of solution?
31. What is the molality of a solution made by dissolving 5.00 g of naphthalene, C10H8, in 50.0 mL of
ethanol? The density of ethanol is 0.790 g/mL.
32. How many grams of NaCl are in 250 g of a 15.0% (by weight) solution?
33. A solution of glucose, C6H12O6, has an osmotic pressure of 7.7 atm at 25°C. What is the molarity of this
solution?
34. Aqueous concentrated nitric acid is 69% HNO3 by weight and has a density of 1.42 g/mL.
a) What is the molality of this solution?
b) What is the molarity of this solution?
35. The vapor pressure of water at 25°C is 23.76 torr. What is the vapor pressure at 25°C of a
solution prepared by dissolving 0.300 mole of sucrose in 12.0 moles of water?
36. What pressure of CO2 gas is required to keep a concentration of dissolved CO2 at 0.10 M in a can of soda?
The Henry’s law constant for CO2 dissolved in water is 0.034 M/atm at 25°C.
37. A saturated solution
a) will dissolve additional solute if more solute is added.
b) contains no dissolved solute.
c) contains dissolved solute in equilibrium with undissolved solid.
d) will rapidly precipitate some solid solute if a seed crystal is added.
38. Which one of the following substances will be the most soluble in water?
a) KBr b) C10H8 c) CCl4 d) C8H18
39. A 0.100 m solution of which one of the following solutes will have the highest boiling point?
a) KNO3 b) Ca(NO3)2 c) Al(NO3)3 d) Na2SO4
40. The freezing point of a 1.0 M solution of NaCl in water is higher than the calculated value that assumes the
particle concentration for this solute is 2.0 M. This is due to
a) solvation of the ions
b) particle concentration greater than 2.0 M
c) hydrogen bonding
d) occurrence of ion pairing
41. When NaCl dissolves in water,
a) the oxygens of the water molecules are attracted to the sodium ions.
b) the hydrogens of the water molecules are attracted to the chloride ions.
c) the sodium and chloride ions becomes separated due to solvation.
d) all of the above are true.
42. What is the freezing point of a solution prepared by dissolving 15 g of KBr in 100 mL of water? The
freezing point depression constant, Kf, for water is 1.86 C/m.