General, Organic, and Biological Chemistry, 3e (Timberlake)
Chapter 5 Compounds and Their Bonds
5.1 Multiple-Choice Questions
1) The number of valence electrons found in an atom of a Group A element is equal to
A) its atomic number.
B) its mass number.
C) its group number.
D) eight.
E) eight minus the group number.
2) Valence electrons are electrons located
A) in the outermost energy level of an atom.
B) in the nucleus of an atom.
C) in the innermost energy level of an atom.
D) throughout the atom.
E) in the first three shells of an atom.
3) In an electron-dot structure of an element, the dots are used to represent
A) all of the electrons in the atom.
B) the valence electrons.
C) the electron arrangement.
D) only the electrons that will participate in bond formation.
E) the electrons that the element will gain when it forms a compound.
4) How many valence electrons are in the electron-dot structures for the elements in group
3A(13)?
A) 1
B) 2
C) 3
D) 4
E) 6
5) The number of electrons in the higher energy level of nitrogen is
A) one.
B) two.
C) three.
D) four.
E) five.
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6) The number of electrons in the higher energy level of carbon is
A) one.
B) two.
C) three.
D) four.
E) five.
7) Which of the following is the correct electron-dot structure for carbon?
A)
B)
C)
D)
E)
8) Which of the following represents the correct Lewis structure for Cl?
A)
B)
C)
D)
E)
9) The octet rule indicates that
A) all of the noble gases have eight total electrons.
B) all of the shells in an atom hold a maximum of 8 electrons.
C) all of the Group A elements have 8 valence electrons.
D) atoms lose, gain, or share valence electrons to have 8 valence electrons.
E) the noble gases react with other compounds to get 8 valence electrons.
10) In ionic compounds, __________ lose their valence electrons to form positively charged
__________.
A) metals; anions
B) nonmetals; cations
C) metals; polyatomic ions
D) nonmetals; anions
E) metals; cations
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11) How many electrons will aluminum gain or lose when it forms an ion?
A) lose 1
B) gain 5
C) lose 2
D) lose 3
E) gain 1
12) What is the symbol for the ion with 19 protons and 18 electrons?
A) F+
B) FC) Ar+
D) KE) K+
13) To form an ion, a sodium atom
A) gains one electron.
B) gains two electrons.
C) loses seven electrons.
D) loses one electron.
E) loses two electrons.
14) An anion always
A) has a positive charge.
B) contains a group of two or more atoms with a positive charge.
C) contains a metal and a nonmetal.
D) forms covalent bonds.
E) has a negative charge.
15) What is the ionic charge of an ion with 18 protons and 15 electrons?
A) 1+
B) 2+
C) 3+
D) 2E) 3-
16) The number of electrons in an ion with 20 protons and an ionic charge of 2 - is
A) 24.
B) 22.
C) 20.
D) 18.
E) 16
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17) Elements in group 2A(2) of the periodic table form ions with a charge of
A) 1+ .
B) 1- .
C) 2+ .
D) 3+.
E) 0.
18) The ion of aluminum is
A) Al+.
B) Al2+.
C) Al3+.
D) Al3-.
E) Al2-.
19) How many electrons will chlorine gain or lose when it forms an ion?
A) lose 1
B) gain 1
C) lose 7
D) gain 2
E) lose 3
20) An ionic compound
A) has a net positive charge.
B) has a net negative charge.
C) contains only cations.
D) contains only anions.
E) has a net charge of zero.
21) The correct formula for a compound formed from the elements Al and O is
A) AlO.
B) Al2O .
C) Al3O2 .
D) AlO3 .
E) Al2O3 .
22) The correct formula for the compound formed from Mg and S is
A) MgS.
B) MgS2.
C) Mg2S.
D) Mg2S2.
E) Mg2S3.
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23) Which one of the following compounds contains an ion with a 3+ charge?
A) KCl
B) Na2O
C) FeCl3
D) CuCl
E) MgCl2
24) What is the correct formula for the oxide ion?
A) O2B) O
C) O+
D) O2+
E) O3+
25) The compound MgCl2 is named
A)
B)
C)
D)
E)
magnesium chlorine.
magnesium dichloride.
magnesium (II) chloride.
magnesium chloride.
dimagnesium chloride.
26) Which one of the following elements forms two or more ions with different ionic charges?
A) K
B) F
C) Ca
D) O
E) Fe
27) What is the correct formula for the iron (II) ion?
A) Fe+
B) Fe2+
C) Fe3+
D) Fe2E) Fe3-
28) The name of the Cu+ ion is
A) copper (II).
B) copper (I).
C) cobalt.
D) copper.
E) cuprum.
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29) What is the correct formula for iron (III) sulfide?
A) Fe2S2
B) Fe2S
C) FeS
D) FeS2
E) Fe2S3
30) A(n) __________ is the smallest neutral unit of two or more atoms held together by a
covalent bond.
A) ionic compound
B) nucleus
C) molecule
D) formula
E) unit
31) In a molecule with covalent bonding,
A) oppositely charged ions are held together by strong electrical attractions.
B) atoms of metals form bonds to atoms of nonmetals.
C) atoms of different metals form bonds.
D) atoms are held together by sharing electrons.
E) atoms of noble gases are held together by attractions between oppositely charged ions.
32) Which of the following elements does NOT exist as a diatomic molecule?
A) hydrogen
B) nitrogen
C) chlorine
D) oxygen
E) carbon
33) In a covalently bonded molecule, the number of electrons that an atom shares with others is
usually equal to the number of electrons
A) in the atom.
B) in its nucleus.
C) in all the atoms.
D) in its ion.
E) needed to give it a noble gas arrangement.
34) Double and triple bonds form because
A) the atoms involved have high electronegativities.
B) single covalent bonds do not give all of the atoms in the molecule eight valence
electrons.
C) one of the atoms in the molecule has more than eight valence electrons.
D) the ions involved have charges larger than one.
E) there is at least one hydrogen atom involved in the bond.
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35) The correct name of the compound NCl3 is
A)
B)
C)
D)
E)
nitrogen chloride.
trinitrogen chloride
nitrogen(III) chloride.
nickel chloride.
nitrogen trichloride
36) The formula for a molecule formed from N and Cl would be
A) NCl.
B) NCl2.
C) NCl3.
D) N3Cl.
E) NCl5.
37) The types of compounds that use prefixes in their names are
A) ionic compounds.
B) ionic compounds involving transition metals.
C) polyatomic ions.
D) covalent compounds.
E) compounds that contain polyatomic ions.
38) The correct name for the compound N2O3 is
A)
B)
C)
D)
E)
nitrogen oxide.
nitrogen trioxide.
dinitride trioxide.
dinitrogen oxide.
dinitrogen trioxide.
39) What is the formula of carbon tetraiodide?
A) CI
B) CI4
C) C4I
D) CI3
E) C2I4
40) The name of Al2(SO4)3 is
A)
B)
C)
D)
E)
aluminum(III) sulfate.
dialuminum trisulfate.
dialuminum sulfate.
dialuminum trisulfide.
aluminum sulfate.
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41) The ability of an atom to attract the shared electrons in a covalent bond is its
A) electronegativity.
B) bonding ability.
C) polarity.
D) ionic character.
E) nonpolarity.
42) Which of the following substances contains a nonpolar covalent bond?
A) H2O
B) NaCl
C) NH3
D) MgF2
E) N2
43) How many valence electrons are in the electron-dot structure of H2O?
A)
B)
C)
D)
E)
2
4
6
8
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44) How many lone pairs of electrons are in the electron-dot structure of H2O?
A)
B)
C)
D)
E)
0
1
2
3
4
45) Choose the best electron-dot structure for OCl2.
A)
B)
C)
D)
E)
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46) Choose the best Lewis structure for CH2Cl2.
A)
B)
C)
D)
E)
47) How many valence electrons are in the electron-dot structure of CCl4?
A)
B)
C)
D)
E)
0
82
6
8
3
48) Which of the following elements has the lowest electronegativity?
A) Li
B) C
C) N
D) O
E) F
49) Which of the following compounds contains a polar covalent bond?
A) NaF
B) HCl
C) Br2
D) MgO
E) O2
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50) Which of the following compounds contains an ionic bond?
A) NH3
B) H2O
C) CaO
D) H2
E) CH4
51) If the electronegativity difference between elements X and Y is 2.1, the bond between the
elements X-Y is
A) ionic.
B) nonpolar ionic.
C) nonpolar covalent.
D) polar covalent.
E) impossible.
52) Ionic bonding is expected in which of these compounds?
A) Cl2
B) KF
C) OF2
D) HF
E) H2
53) A polar covalent bond is found in which of these compounds?
A) H2O
B) F2
C) NaCl
D) H2
E) N2
54) The bond in Cl2 is a(n)
A)
B)
C)
D)
E)
ionic bond.
nonpolar covalent bond.
metallic bond.
polar ionic bond.
no bond.
55) A group of covalently bonded atoms that has an overall electrical charge is called a(n)
A) ionic compound.
B) anion.
C) polyatomic ion.
D) cation.
E) molecule.
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56) Which of the following polyatomic ions has a positive charge?
A) hydroxide
B) sulfate
C) hydrogen carbonate
D) ammonium
E) nitrate
57) Which of the following polyatomic ions has a 3- ionic charge?
A) hydroxide
B) nitrate
C) sulfate
D) phosphate
E) bicarbonate
58) What is the formula of the nitride ion?
A) N 3
B) NO2C) NO33D) NO32E) NO3-
59) The name of the HSO4- ion is
A)
B)
C)
D)
E)
sulfate.
hydrogen sulfate.
sulfite.
hydrogen sulfite.
sulfide.
60) What is the formula of a compound that contains Na+ and PO 3- ions?
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A) Na3PO4
B) NaPO4
C) Na2PO3
D) Na3PO34
E) Na3P
61) Fe2(SO4)3 is called
A) iron sulfate.
B) iron (II) sulfate.
C) iron (III) sulfate.
D) diiron trisulfate.
E) iron trisulfate.
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62) What is the formula for aluminum nitrite?
A) Al2NO2
B) AlNO3
C) Al(NO2)3
D) Al2(NO3)3
E) Al2(NO2)2
63) The VSEPR theory allows us to determine the most favorable
A) shape of a molecule.
B) charge on an ion.
C) color of a compound.
D) bond type for a molecule.
E) formula for a compound.
64) The shape of the carbon tetrachloride molecule is
A) linear.
B) square.
C) pyramidal.
D) tetrahedral.
E) octagonal.
65) The water molecule has a dipole with the negative portion
A) localized between the hydrogen atoms.
B) pointing toward the oxygen atom.
C) localized on one of the hydrogens.
D) pointing from the oxygen through the hydrogen atoms.
E) surrounding the molecule.
66) When a cation is formed from a representative element
A) electrons are gained and the ion is larger.
B) electrons are gained and the ion is smaller.
C) electrons are lost and the ion is larger.
D) electrons are lost and the ion is smaller.
E) the cation acquires a negative charge.
67) The shape of the ammonia molecule ( NH3 ) is
A)
B)
C)
D)
E)
linear.
square.
pyramidal.
hexagonal.
octagonal.
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68) The shape of the carbon dioxide (CO2 ) is
A)
B)
C)
D)
E)
linear.
square.
pyramidal.
hexagonal.
bent.
69) The shape of the water molecule ( H2O) is
A)
B)
C)
D)
E)
linear.
tetrahedral.
pyramidal.
bent
octagonal.
70) The carbon tetrachloride molecule, CCl4, has the shape of a
A)
B)
C)
D)
E)
tetrahedron.
square.
cube.
circle.
sphere.
71) Hydrogen sulfide, H2S, has a shape similar to
A)
B)
C)
D)
E)
carbon dioxide.
carbon monoxide.
hydrogen chloride.
water.
carbon tetrachloride.
72) The main type of interaction between molecules of ammonia ( NH3 ) are
A)
B)
C)
D)
E)
ionic bonds.
hydrogen bonds.
polar covalent.
dipole-dipole.
dispersion forces.
73) The main type of interaction between molecules of hydrogen ( H2 ) are
A)
B)
C)
D)
E)
ionic bonds.
hydrogen bonds.
polar covalent.
dipole-dipole.
dispersion forces.
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74) The carbon tetrachloride molecule, CCl4, is
A)
B)
C)
D)
E)
a polar molecule with polar bonds.
a nonpolar molecule with polar bonds.
a nonpolar molecule with nonpolar bonds.
a polar molecule with nonpolar bonds.
a polar molecule with ionic bonds.
75) The ammonia molecule ( NH3 ) is
A)
B)
C)
D)
E)
a polar molecule with polar bonds.
a nonpolar molecule with polar bonds.
a nonpolar molecule with nonpolar bonds.
a polar molecule with nonpolar bonds.
a polar molecule with ionic bonds.
76) The main interactions between molecules of hydrogen chloride are examples of
A) ionic bonds.
B) covalent bonds.
C) hydrogen bonds.
D) dipole-dipole interactions.
E) dispersion forces.
77) The main interactions between molecules of hydrogen H2 are examples of
A) ionic bonds.
B) covalent bonds.
C) hydrogen bonds.
D) dipole-dipole interactions.
E) dispersion forces.
5.2 Short Answer Questions
Identify each of the following compounds as polar or nonpolar.
1) carbon tetrachloride
2) water
3) carbon dioxide
4) hydrogen sulfide
5) hydrogen fluoride
6) carbon monoxide
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Identify each of the following compounds as covalent or ionic.
7) nitrogen trichloride
8) carbon tetrachloride
9) potassium oxide
10) carbon dioxide
11) sodium fluoride
12) dihydrogen sulfide
13) The weakest type of force between particles of a substance is termed __________.
14) Are hydrogen bonds stronger or weaker than covalent bonds?
15) Are dipole-dipole interactions weak or strong compared to ionic bonds?
5.3 Matching Questions
Match the correct name of the polyatomic ions with the formulas given.
1) NO32) CO32-
A) hydrogen sulfite
3) SO42-
C) hydrogen sulfate
4) SO325) PO43-
B) carbonite
D) hydroxide
E) oxide
F) phosphate
6)
G) carbonate
7)
H) sulfate
8)
I) sulfite
9)
J) nitrite
K) hydrogen carbonate
L) phosphite
M) nitrate
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Give the correct charge for ions of the following elements.
10) Ca
A) 0
11) Cl
B) 3+
12) O
13) Al
14) K
C)
D)
E)
21+
1-
F) 2+
Indicate the type of bonding you would expect between the following elements.
15) Na and F
A) ionic
16) N and F
B) none
17) F and F
C) polar covalent
18) He and F
D) nonpolar covalent
19) H and F
Match the chemical name with the correct formula.
20) magnesium sulfate
A) MgSO4
21) magnesium hydrogen sulfate
22) magnesium sulfide
23) magnesium sulfite
B) MgSO3
C) MgS
D) Mg(HSO4)2
24) magnesium hydrogen sulfite
E) Mg(HSO3)
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