AP Chemistry Unit 2 Exam Questions
with Accurate Answers
Which of the following claims about a binary compound in which the bonding is ionic is
most likely to be scientifically correct?
A. Both elements in the compound are metals.
B. The electronegativity difference between the elements in the compound is relatively
large.
C. The atomic masses of the elements in the compound are relatively small.
D. There is an equal sharing of electrons between the atoms of the elements in the
compound. - ANSWERSB. The electronegativity difference between the elements in the
compound is relatively large.
Molten (liquid) NaCl is represented by the particulate diagram shown above. Which of
the following indicates whether NaCl (l) conducts electricity and best explains why or
why not?
A. It conducts electricity because Na is a metal.
B. It does not conduct electricity because Cl is a nonmetal.
C. It conducts electricity because ions are free to move.
D. It does not conduct because there are no free electrons. - ANSWERSC. It conducts
electricity because ions are free to move.
Which of the diagrams above best represents the CH2O molecule, and why?
A. Diagram 1, because all bond angles are 180o.
B. Diagram 1, because all atoms have a formal charge of 0.
C. Diagram 2, because all atoms have a formal charge of 0.
D. Diagram 2, because the molecule has a trigonal pyramidal shape. - ANSWERSC.
Diagram 2, because all atoms have a formal charge of 0.
Based on the Lewis electron-dot diagram for NH3 shown above, the H-N-H bond angle
is closest to which of the following?
A. 120 degrees
B. 109.5 degrees
C. 90 degrees
D. 60 degrees - ANSWERSB. 109.5 degrees
Which of the following correctly compares the strength of the two carbon-to-carbon
bonds in the molecule represented in the Lewis electron-dot diagram above?
, A. The carbon-to-carbon bonds are the same strength because the C-C-C bond angles
is 180o.
B. The carbon-to-carbon bonds are the same strength because they are both bonds
between carbon atoms.
C. The carbon-to-carbon bond on the right is stronger because there are more hydrogen
atoms attached to the rightmost carbon atom than to the leftmost carbon atom.
D. The carbon-to-carbon bond on the left is stronger because it is a double bond. -
ANSWERSD. The carbon-to-carbon bond on the left is stronger because it is a double
bond.
Based on the data in the tables below, which of the following statements provides the
best prediction for the boiling point of NaCl?
NaF MgO
Boiling point (degrees C) 1695 3600
Na+ Mg2+ F- Cl- O2-
Ionic radius (pm) 76 72 133 181 140
A. NaCl will have a lower boiling point than NaF because the coulombic attractions are
weaker in NaCl than in NaF.
B. NaCl will have a boiling point between that of NaF and MgO because the covalent
character of the bonds in NaCl is intermediate between that of MgO and NaF.
C. NaCl will have a higher boiling point than MgO because the ions are spaced farther
apart in NaCl.
D. NaCl will have a higher boiling point than MgO because the energy required to
transfer electrons from the anion to the cation is larger in NaCl than in MgO. -
ANSWERSA. NaCl will have a lower boiling point than NaF because the coulombic
attractions are weaker in NaCl than in NaF.
The potential energy as a function of internuclear distance for three diatomic molecules
X2,, Y2, and Z2, is shown in the graph above. Based on the data in the graph, which of
the following correctly identifies the diatomic molecules, X2,, Y2, and Z2 ?(2014)
X2, Y2 Z2
A. H2 O2 N2
B. N2 O2 H2
C. H2 N2 O2
D. O2 H2 N2 - ANSWERSC. H2 N2 O2
The figure above shows that in solid hydrogen fluoride there are two different distances
between H atoms and F atoms. Which of the following best accounts for the two
different distances?
A. Accommodation of the necessary bond angles in the formation of the solid.
with Accurate Answers
Which of the following claims about a binary compound in which the bonding is ionic is
most likely to be scientifically correct?
A. Both elements in the compound are metals.
B. The electronegativity difference between the elements in the compound is relatively
large.
C. The atomic masses of the elements in the compound are relatively small.
D. There is an equal sharing of electrons between the atoms of the elements in the
compound. - ANSWERSB. The electronegativity difference between the elements in the
compound is relatively large.
Molten (liquid) NaCl is represented by the particulate diagram shown above. Which of
the following indicates whether NaCl (l) conducts electricity and best explains why or
why not?
A. It conducts electricity because Na is a metal.
B. It does not conduct electricity because Cl is a nonmetal.
C. It conducts electricity because ions are free to move.
D. It does not conduct because there are no free electrons. - ANSWERSC. It conducts
electricity because ions are free to move.
Which of the diagrams above best represents the CH2O molecule, and why?
A. Diagram 1, because all bond angles are 180o.
B. Diagram 1, because all atoms have a formal charge of 0.
C. Diagram 2, because all atoms have a formal charge of 0.
D. Diagram 2, because the molecule has a trigonal pyramidal shape. - ANSWERSC.
Diagram 2, because all atoms have a formal charge of 0.
Based on the Lewis electron-dot diagram for NH3 shown above, the H-N-H bond angle
is closest to which of the following?
A. 120 degrees
B. 109.5 degrees
C. 90 degrees
D. 60 degrees - ANSWERSB. 109.5 degrees
Which of the following correctly compares the strength of the two carbon-to-carbon
bonds in the molecule represented in the Lewis electron-dot diagram above?
, A. The carbon-to-carbon bonds are the same strength because the C-C-C bond angles
is 180o.
B. The carbon-to-carbon bonds are the same strength because they are both bonds
between carbon atoms.
C. The carbon-to-carbon bond on the right is stronger because there are more hydrogen
atoms attached to the rightmost carbon atom than to the leftmost carbon atom.
D. The carbon-to-carbon bond on the left is stronger because it is a double bond. -
ANSWERSD. The carbon-to-carbon bond on the left is stronger because it is a double
bond.
Based on the data in the tables below, which of the following statements provides the
best prediction for the boiling point of NaCl?
NaF MgO
Boiling point (degrees C) 1695 3600
Na+ Mg2+ F- Cl- O2-
Ionic radius (pm) 76 72 133 181 140
A. NaCl will have a lower boiling point than NaF because the coulombic attractions are
weaker in NaCl than in NaF.
B. NaCl will have a boiling point between that of NaF and MgO because the covalent
character of the bonds in NaCl is intermediate between that of MgO and NaF.
C. NaCl will have a higher boiling point than MgO because the ions are spaced farther
apart in NaCl.
D. NaCl will have a higher boiling point than MgO because the energy required to
transfer electrons from the anion to the cation is larger in NaCl than in MgO. -
ANSWERSA. NaCl will have a lower boiling point than NaF because the coulombic
attractions are weaker in NaCl than in NaF.
The potential energy as a function of internuclear distance for three diatomic molecules
X2,, Y2, and Z2, is shown in the graph above. Based on the data in the graph, which of
the following correctly identifies the diatomic molecules, X2,, Y2, and Z2 ?(2014)
X2, Y2 Z2
A. H2 O2 N2
B. N2 O2 H2
C. H2 N2 O2
D. O2 H2 N2 - ANSWERSC. H2 N2 O2
The figure above shows that in solid hydrogen fluoride there are two different distances
between H atoms and F atoms. Which of the following best accounts for the two
different distances?
A. Accommodation of the necessary bond angles in the formation of the solid.
