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chemistry chapter 4

1.

1) The nature of bonding forces in matter influences which of the following observable properties of the matter?

A) the optical property

B) the state of the matter at room temperature

C) the strength and rigidity

D) all of the above

d

2.

2) The noble gases are inert. This means they

  1. A) undergo very few chemical reactions.
  2. B) exist as gases at room temperature.
  3. C) undergo many chemical reactions.
  4. D) lose and gain electrons easily.



A

3.

3) The inertness of the noble gases is due to

A) the outermost shell has six electrons.

B) the number of protons and neutrons.

C) the bonds they form with other elements.

D) the outermost shell has an octet of electrons, except for helium which has two electrons.

D

4.

4) A sodium ion, Na+, has the same electron configuration as a(n)

  1. A) sodium atom.
  2. B) chlorine atom.
  3. C) neon atom.
  4. D) argon atom.



C

5.

5) A chloride ion, Cl- has the same electron configuration as a(n)

  1. A) sodium atom.
  2. B) chlorine atom.
  3. C) neon atom.
  4. D) argon atom.



D

6.

6) The number of electrons in a chloride ion, Cl-, is

  1. A) 16.
  2. B) 17.
  3. C) 18.
  4. D) 35.



C

7.

7) The number of protons in a chloride ion, Cl-, is

  1. A) 16.
  2. B) 17.
  3. C) 18.
  4. D) 35.



B

8.

8) The number of electrons in a sodium ion, Na+, is

  1. A) 10.
  2. B) 11.
  3. C) 12.
  4. D) 23.



A

9.

9) The number of protons in a sodium ion, Na+, is

  1. A) 10.
  2. B) 11.
  3. C) 12.
  4. D) 23.



B

10.

10) When calcium reacts with iodine, calcium ions, Ca2+, and iodide ions, I-, are formed. In this reaction, calcium atoms

  1. A) lose electrons.
  2. B) gain electrons.
  3. C) lose protons.
  4. D) gain protons.



A

11.

11) When barium reacts with iodine, barium ions, Ba2+, and iodide ions, I-, are formed. In this reaction, iodine atoms

  1. A) lose electrons.
  2. B) gain electrons.
  3. C) lose protons.
  4. D) gain protons.



B

12.

12) When atoms lose or gain electrons in chemical reactions they form

A) new atoms.

B) noble gases.

C) nucleons.

D) ions.

D

13.

13) Which molecule is **NOT** likely to exist?

  1. A) N2
  2. B) Br2
  3. C) CI4
  4. D) Ar2



D

14.

14) Noble gases are unreactive because of their electronic structures. The kind of reasoning that states "if other elements could be made to achieve noble gas electronic structures they would be more stable" is called

A) logic.

B) inductive reasoning.

C) deductive reasoning.

D) critical thinking.

C

15.

15) Mg2+ has the same electronic structure as

  1. A) Ne.
  2. B) Mg.
  3. C) C.
  4. D) Ar.



A

16.

16) The number of electrons in a sulfide ion, S2-, is

  1. A) 16.
  2. B) 14.
  3. C) 18.
  4. D) 32.



C

17.

17) Which of the following molecules is **NOT** likely to exist?

  1. A) CO2
  2. B) HCl
  3. C) CCl4
  4. D) RnH



D

18.

18) Which of the following pairs is isoelectronic?

  1. A) Ar and Ne
  2. B) Ar and Na+
  3. C) Ar and F-
  4. D) Ar and S2-



D

19.

19) All of the following pairs are isoelectronic **EXCEPT**

  1. A) Ne and Rn.
  2. B) Rb+and Sr2+.
  3. C) Ne and Mg2+.
  4. D) F-and Ne.



A

20.

20) All of the following species are isoelectronic to Mg2+ **EXCEPT**

  1. A) Li+.
  2. B) Na+.
  3. C) Ne.
  4. D) O2-.



A

21.

21) With respect to chemical bonding, which particles play the most active role?

A) protons

B) neutrons

C) valence electrons

D) core electrons

C

22.

22) An electron-dot structure is a convenient method of representing

A) valence electrons of an atom.

B) core electrons of an atom.

C) all electrons of the atom.

D) the complete electron configuration of the atom.

A

23.

23) From the periodic table, the number of valence electrons for most of the main group elements may be determined directly from the

A) atomic number.

B) group number.

C) period number.

D) nucleon number.

B

24.

24) Which is the electron dot structure of magnesium?

  1. A) Mg



B)

C)

D)

C

25.

29) Where does an element X with the electron dot structure

fit in the periodic table?

  1. A) Group 1A
  2. B) Group 2A
  3. C) Group 3A
  4. D) Group 5A



C

26.

30) An element with 7 electrons in its outer shell is in which group on the periodic table?

A) Group 5A

B) Group 7A

C) Group 6A

D) Group 2A

B

27.

31) Which of the noble gases does**NOT** have an octet of electrons in its outer shell?

A) He

B) Ne

C) Ar

D) Kr

A

28.

32) In a Lewis formula, the dots represent

A) all the electrons in the atoms.

B) the valence electrons in all the atoms.

C) only the electrons that are being transferred or shared.

D) whatever number of electrons are needed to satisfy the octet rule.

B

29.

33) With respect to chemical bonding, which particles play the **least** active role?

A) nucleons

B) core electrons

C) valence electrons

D) All play equal roles.

A

30.

34) How many dots will appear in the Lewis dot structure for an element from in Group 1A of the periodic table?

A) five

B) eight

C) one

D) four

C

31.

35) Why do chemists use the Lewis symbols to represent chlorine and sodium rather than drawing the electron diagrams of each element before and after the reaction?

A) Lewis symbols are easier to use.

B) Lewis symbols are more scientific.

C) Lewis symbols are more accurate.

D) Lewis symbols are more abstract.

A

32.

36) When a freshly cut piece of sodium metal, Na, is dropped into a flask with chlorine gas, a violent reaction takes place creating a new compound. This compound

  1. A) has properties that are more like Na than Cl.
  2. B) has properties that are totally unlike either Na or Cl.
  3. C) has properties that more like Cl than Na.
  4. D) has properties that are like both Cl and Na.



B

33.

37) An anion is

A) an element that has lost protons.

B) an element that has gained protons.

C) an element that has lost electrons.

D) an element that have gained electrons.

D

34.

38) The attraction between positive and negative ions is known as a(n)

A) covalent bond.

B) crystal bond.

C) ionic bond.

D) molecular bond.

C

35.

39) When ions arrange themselves in an orderly structure, that structure is known as a

A) crystal.

B) dipole.

C) molecule.

D) tetrahedron.

A

36.

40) When magnesium combines with bromine, the bond formed is best classified as

A) ionic.

B) polar covalent

C) metallic.

D) nonpolar covalent.

A

37.

41) Which substance has ionic bonds?

  1. A) O2
  2. B) BaO
  3. C) H2O
  4. D) OF2



B

38.

42) Which substance has ionic bonds?

  1. A) Br2
  2. B) NH3
  3. C) H2O
  4. D) LiI



D

39.

43) Which substance has ionic bonds?

  1. A) K2S
  2. B) SO3
  3. C) CI4
  4. D) N2



A

40.

44) Which pair of atoms would form an ionic bond?

  1. A) Na and Mg
  2. B) Ca and S
  3. C) Cl and Br



D) N and N

B

41.

45) A sodium ion is

  1. A) Na+.
  2. B) Na2+.
  3. C) Na-.
  4. D) Na2-.



A

42.

46) A iodide ion is

  1. A) I+.
  2. B) I2+.
  3. C) I-.
  4. D) I2-.



C

43.

47) An oxide ion is

  1. A) O+.
  2. B) O2+.
  3. C) O-.
  4. D) O2-.



D

44.

48) A nitride ion is

  1. A) N+.
  2. B) N3+.
  3. C) N2-.
  4. D) N3-.



D

45.

49) Chlorine forms monatomic ions with a charge of

A) 1-.

B) 1+.

C) 2-.

D) 2+.

A

46.

50) Oxygen forms monatomic ions with a charge of

A) 2+.

B) 3+.

C) 1-.

D) 2-.

D

47.

51) Which atom is least likely to form an ion?

A) chlorine

B) sodium

C) carbon

D) oxygen

C

48.

52) Which atom is least likely to form an ion?

A) bromine, Br

B) phosphorus, P

C) aluminum, Al

D) carbon, C

D

49.

53) Calcium reacts with chloride to form

  1. A) CaCl.
  2. B) CaCl2.
  3. C) Ca2
  4. D) Ca2Cl3.



B

50.

54) Magnesium reacts with oxygen to form

  1. A) MgO.
  2. B) Mg2
  3. C) MgO2.
  4. D) Mg3O2.



A

51.

55) Potassium reacts with iodine to form

  1. A) KI.
  2. B) K2
  3. C) KI2.
  4. D) K2I3.



A

52.

56) When magnesium combines with oxygen, the reaction involves a

A) transfer of electrons from Mg to O.

B) transfer of electrons from O to Mg.

C) sharing of electrons between Mg and O.

D) conversion of protons into electrons.

A

53.

57) When magnesium reacts with chlorine, the reaction involves a

A) transfer of electrons from Mg to Cl.

B) transfer of electrons from Cl to Mg.

C) sharing of electrons between Mg and Cl.

D) creation of electrons.

A

54.

58) When calcium reacts with chlorine, the reaction involves a

A) transfer of electrons from Ca to Cl.

B) transfer of electrons from Cl to Ca.

C) sharing of electrons between Ca and Cl.

D) creation of electrons.

A

55.

59) In reactions to form ionic compounds, metals generally

A) lose electrons.

B) gain electrons.

C) become non-metals.

D) do not react.

A

56.

60) In reactions to form ionic compounds, nonmetals generally

A) lose electrons.

B) gain electrons.

C) become metals.

D) do not react.

B

57.

61) Octet means

A) stable electrons.

B) valence electrons.

C) eight.

D) filled shell.

C

58.

62) The cation formed when a sodium atom loses an electron is called the

A) sodide ion.

B) sodate ion.

C) sodium ion.

D) soda ion.

C

59.

63) The anion formed when oxygen gains two electrons is called the

A) oxygen ion.

B) oxyide ion.

C) oxide ion.

D) oxy ion.

C

60.

64) The anion formed when nitrogen gains three electrons is called the

A) nitride ion.

B) nitrite ion.

C) nitrogide ion.

D) nitro ion.

A

61.

65) For which atom is it difficult to predict the most probable ionic charge using the periodic table?

A) Co

B) K

C) Al

D) Br

A

62.

66) For which atom is it difficult to predict the most probable ionic charge using the periodic table?

A) H

B) Fe

C) O

D) Ne

B

63.

67) The name of the compound with the formula AlCl3 is

  1. A) aluminum(III) chloride.
  2. B) aluminum trichloride.
  3. C) monoaluminum trichlorine.
  4. D) aluminum chloride.



D

64.

68) The formula of aluminum oxide is

  1. A) AlO.
  2. B) AlO2.
  3. C) AlO3.
  4. D) Al2O3.



D

65.

69) The formula of magnesium nitride is

  1. A) Mg3N2.
  2. B) Mg2N3.
  3. C) Mg2
  4. D) MgN.



A

66.

70) An ionic bond is formed when electrons are

A) transferred.

B) shared.

C) split.

D) destroyed.

A

67.

71) The formula for the compound calcium bromide is

  1. A) CaBr.
  2. B) Ca2
  3. C) CaBr2.
  4. D) Ca3Br2.



C

68.

72) Which of the following is a binary compound?

  1. A) HCN
  2. B) O2
  3. C) LiBr
  4. D) Na2SO4



C

69.

73) How many electrons are there in a double bond?

A) 1

B) 2

C) 4

D) 6

C

70.

74) The name of the compound S2O3 is

  1. A) disulfur oxide.
  2. B) disulfur trioxide.
  3. C) sulfur oxide.
  4. D) sulfur trioxide.



B

71.

75) The prefix which means seven is

A) hexa.

B) hepta.

C) octa.

D) tetra.

B

72.

76) A covalent bond is formed when a pair of electrons is

A) transferred.

B) shared.

C) split.

D) destroyed.

B

73.

77) Covalent bonds generally form between

A) ions.

B) metals.

C) metals and nonmetals.

D) nonmetals.

D

74.

78) If two atoms from the same element share three pairs of electrons in forming a molecule the bond is called a

A) single covalent bond.

B) double covalent bond.

C) triple covalent bond.

D) coordinate covalent bond.

C

75.

79) In a molecule of nitrogen, N2, the nitrogen atoms are bonded to each other by

  1. A) an ionic bond.
  2. B) a single covalent bond.
  3. C) a double covalent bond.
  4. D) a triple covalent bond.



D

76.

81) What is the name of the compound with the formula CF4?

  1. A) carbon fluoride
  2. B) carbon(IV) fluoride
  3. C) fluorine carbonide
  4. D) carbon tetrafluoride



D

77.

82) What is the name of the compound with the formula SO3?

  1. A) sulfur(VI) oxide
  2. B) sulfur oxide(III)
  3. C) sulfur trioxide
  4. D) sulfur(I) oxide(III)



C

78.

83) The compound dinitrogen trioxide would have the chemical formula

  1. A) NO3.
  2. B) N3O2.
  3. C) N2O3.
  4. D) N2O5.



C

79.

84) Hydrogen is a diatomic molecule, H2. The bond holding the hydrogen atoms together is

  1. A) ionic.
  2. B) nonpolar covalent.
  3. C) polar covalent.
  4. D) metallic.



B

80.

85) In a nonpolar covalent bond, electrons are

A) shared equally.

B) shared unequally.

C) transferred.

D) uncharged.

A

81.

86) ________ is the measure of the tendency of an atom in a molecule to attract a shared pair of electrons to itself.

A) Ionization

B) Electronegativity

C) Polarity

D) Precipitation

B

82.

87) Which one of the following has the **LOWEST** electronegativity?

A) sodium

B) oxygen

C) chlorine

D) fluorine

A

83.

88) In the hydrogen chloride molecule, HCl, the chlorine end of the molecule is more negative than the hydrogen end because

A) chlorine is more electronegative than hydrogen.

B) hydrogen is more electronegative than chlorine.

C) hydrogen and chlorine have the same electronegativity.

D) hydrogen transfers an electron to chlorine.

A

84.

89) In a covalent bond, the shared electrons are sometimes referred to as

A) core electrons.

B) bonding pairs.

C) nonbonding pairs.

D) neutral pairs.

B

85.

90) Which substance has nonpolar covalent bonds?

  1. A) H2
  2. B) NO2
  3. C) NaBr
  4. D) CO



A

86.

91) Which substance has polar covalent bonds?

  1. A) SO2
  2. B) N2
  3. C) F2
  4. D) BaO



A

87.

92) Which substance has polar covalent bonds?

  1. A) Rn
  2. B) NH3
  3. C) F2
  4. D) Ca2C



B

88.

93) When two chlorine atoms combine with each other, the bond that forms is

A) ionic.

B) polar covalent.

C) nonpolar covalent.

D) ionic covalent.

C

89.

94) The most electronegative atom is

A) Cl.

B) F.

C) Na.

D) I.

B

90.

95) When a fluorine atom reacts with a chlorine atom, the bond that forms between them should be

A) ionic.

B) polar covalent.

C) nonpolar covalent.

D) ionic covalent.

B

91.

96) Which substance has covalent bonds?

  1. A) KF
  2. B) NaF
  3. C) MgI2
  4. D) CO2



D

92.

97) In a polar covalent bond, electrons are

A) shared equally.

B) shared unequally.

C) transferred.

D) uncharged.

B

93.

98) Which of the following elements has the highest electronegativity?

A) O

B) H

C) Cl

D) F

D

94.

99) Which of the following elements has the lowest electronegativity?

A) K

B) Kr

C) Br

D) Se

B

95.

100) Which of the following pairs of atoms will form a polar covalent bond?

A) Ne and Ar

B) H and O

C) H and C

D) C and C

B

96.

101) A nonpolar covalent bond will form between atoms that have an electronegativity difference of

A) < 0.5.

B) between 0.5 and 1.5.

C) between 1.0 and 2.0.

D) > 2.0.

A

97.

102) Which of the following atoms will have the lowest electronegativity value?

A) an atom with 1 valence electron

B) an atom with 3 valence electrons

C) an atom with 5 valence electrons

D) an atom with 7 valence electrons

A

98.

103) Hydrogen and carbon react to form

  1. A) CH.
  2. B) CH2.
  3. C) CH3.
  4. D) CH4.



D

99.

104) Hydrogen and nitrogen react to form

  1. A) NH.
  2. B) NH2.
  3. C) NH3.
  4. D) NH4.



C

100.

105) Hydrogen and sulfur react to form

  1. A) HS.
  2. B) H2
  3. C) HS2.
  4. D) H4S2.



B

101.

106) Water is the common name for which molecule?

  1. A) H2O
  2. B) HO2
  3. C) HO
  4. D) H2O2



A

102.

107) Methane is the common name for which molecule?

  1. A) NH3
  2. B) CH4
  3. C) HF
  4. D) CF4



B

103.

108) The common name of the compound with the formula NH3 is

  1. A) ammonia.
  2. B) vinegar.
  3. C) methane.
  4. D) alcohol.



A

104.

109) An atom with four valence electrons will form ________ bond(s) with other atoms.

A) 0

B) 1

C) 4

D) 3

C

105.

110) What is the formula of ammonium nitrate?

  1. A) NH4NO3
  2. B) (NH4)2NO3
  3. C) NH4(NO3)2
  4. D) NH4N



A

106.

111) Sodium hydroxide is commonly known as lye. The formula of sodium hydroxide is

  1. A) NaOH.
  2. B) Na2
  3. C) Na(OH)2.
  4. D) SOH.



A

107.

112) Chalk is primarily composed of calcium carbonate. The formula of calcium carbonate is

  1. A) CaCO3.
  2. B) Ca2CO3.
  3. C) Ca(CO3)2.
  4. D) Ca3(CO3)2.



A

108.

113) The formula of iron(II) phosphate is

  1. A) FePO4.
  2. B) Fe2PO4.
  3. C) Fe2(PO4)3.
  4. D) Fe3(PO4)2.



D

109.

114) What is the name of NaH2PO4?

  1. A) sodium hydrogen phosphate
  2. B) sodium dihydrogen phosphate
  3. C) monosodium dihydrogen monophosphate
  4. D) sodium(II) dihydrogen monophosphate



B

110.

115) In the formula for copper(II) phosphate, the number of phosphorus atoms is

A) one.

B) two.

C) three.

D) four.

B

111.

116) In the formula for ammonium nitrate, the number of nitrogen atoms is

A) one.

B) two.

C) three.

D) four.

B

112.

117) How many phosphorus atoms are in the formula for potassium dihydrogen phosphate?

A) 1

B) 2

C) 3

D) 4

A

113.

118) How many iron atoms are in the formula for iron(III) oxide?

A) 1

B) 2

C) 3

D) 4

B

114.

119) How many oxygen atoms are in the formula for iron(III) oxide?

A) 1

B) 2

C) 3

D) 4

C

115.

120) How many magnesium atoms are in the formula for magnesium nitride?

A) 1

B) 2

C) 3

D) 4

C

116.

121) How many nitrogen atoms are in the formula for magnesium nitride?

A) 1

B) 2

C) 3

D) 4

B

117.

122) The formula of sodium chromate is

  1. A) NaCrO4.
  2. B) Na2
  3. C) Na2CrO4.
  4. D) Na3(CrO4)2.



C

118.

123) Which of the following is a polyatomic ion?

  1. A) HCN
  2. B) Na+
  3. C) H2
  4. D) SO42-



D

119.

124) The chemical formula for silver sulfate is

  1. A) AgSO4.
  2. B) Ag2SO4.
  3. C) Ag(SO4)2.
  4. D) Ag3SO4.



B

120.

125) The correct formula for lithium acetate is

  1. A) LiC2H3O2.
  2. B) Li3C2H3O2.
  3. C) Li2C2O3H2.
  4. D) Li(C2H3O2)2.



A

121.

126) The correct formula for the nitrite ion is

  1. A) NO3-.
  2. B) NO32-.
  3. C) NO22-.
  4. D) NO2-.



D

122.

127) The correct formula for iron(III) carbonate is

  1. A) FeCO3.
  2. B) Fe2CO3.
  3. C) Fe3CO3.
  4. D) Fe2(CO3)3.



D

123.

128) NO2- is the ________ ion.

  1. A) ammonium
  2. B) cyanide
  3. C) nitrate
  4. D) nitrite



D

124.

131) The structure of formaldehyde, CH2O, has

  1. A) all ionic bonds.
  2. B) all single covalent bonds.
  3. C) a double covalent bond between carbon and oxygen.
  4. D) a triple covalent bond between carbon and oxygen.



c

125.

132) Acetylene is used in high temperature metal cutting torches. The formula of acetylene is C2H2. The structure of acetylene is

  1. A) H—C—C—H.
  2. B) H—CC—H.
  3. C) H—CC—H.
  4. D) C—HH—C.



C

126.

133) When a phosphorus atom combines with hydrogen to form a molecule, how many bonds are formed?

A) 1

B) 2

C) 4

D) 3

D

127.

134) Which of the following elements can form four bonds with other atoms?

A) S

B) Br

C) Si

D) P

C

128.

135) Which one of the following compounds does **NOT** obey the "octet rule"?

  1. A) H2O
  2. B) CBr4
  3. C) LiF
  4. D) BF3



D

129.

136) Which one of the following compounds does **NOT** obey the "octet rule"?

  1. A) CO2
  2. B) CH4
  3. C) SCl6
  4. D) NH3



C

130.

137) Atoms and molecules with odd numbers of electrons are called

  1. A) ions.
  2. B) odd.
  3. C) covalent.



D) free radicals

D

131.

138) The number of electrons contained in several molecules and ions is shown below. Which of the following is most likely to be a free radical?

  1. A) 12
  2. B) 13
  3. C) 16
  4. D) 18



B

132.

139) Which one of the following is a free radical?

  1. A) H2S
  2. B) NO
  3. C) NH3
  4. D) CF4



B

133.

140) The valence shell electron pair repulsion theory (VSEPR) is used to

A) predict the bonding pattern in molecules.

B) predict the three dimensional structure of molecules.

C) predict the electronegativity of atoms.

D) predict the number of multiple bonds in a molecule.

B

134.

141) If a central atom has a total of two electron sets and no lone pairs attached to it, the geometry about the central atom is

A) linear.

B) trigonal planar.

C) tetrahedral.

D) pyramidal.

A

135.

142) If a central atom has a total of three electron sets and no lone pairs attached to it, the geometry about the central atom is

A) linear.

B) trigonal planar.

C) tetrahedral.

D) pyramidal.

B

136.

143) If a central atom has four electron sets attached to it, the geometry about the central atom is

A) linear.

B) trigonal planar.

C) tetrahedral.

D) pyramidal.

C

137.

144) The VSEPR theory is based on

A) the neutralization of ionic charge in a molecule.

B) the minimization of repulsion among valence electron pairs.

C) the arrangement of core electrons in a molecule.

D) the loss and gain of electrons based on electronegativity.

B

138.

145) The shape of a water molecule is

A) linear.

B) bent.

C) tetrahedral.

D) trigonal planar.

B

139.

146) The shape of a methane molecule is best described as

A) linear.

B) trigonal planar.

C) bent.

D) tetrahedral.

D

140.

147) The best description of the shape of an ammonia molecule is

A) linear.

B) bent.

C) trigonal pyramidal.

D) tetrahedral.

C

141.

148) The best description of the shape of a boron trifluoride (BF3) molecule is

  1. A) pyramidal.
  2. B) trigonal planar.
  3. C) tetrahedral.
  4. D) linear.



B

142.

149) The shape of the carbon dioxide molecule is

A) pyramidal.

B) trigonal planar.

C) tetrahedral.

D) linear.

D

143.

150) The shape of the sulfur dioxide molecule, where sulfur is the central atom is

A) linear.

B) bent.

C) trigonal planar.

D) tetrahedral.

B

144.

151) A central atom that has tetrahedral geometry will have a total of

A) 4 electron sets and 0 lone pairs.

B) 3 electron sets and 1 lone pairs.

C) 2 electron sets and 1 lone pairs.

D) 3 electron sets and 0 lone pairs.

A

145.

152) Interaction between molecules caused by the geometric orientations of their atoms is known as

A) medicinal chemistry.

B) molecular recognition.

C) polar recognition.

D) the VESPR effect.

B

146.

153) A molecule that has a partial positive charge on one end and a partial negative charge on the other end is a

A) dipole.

B) nonpolar molecule.

C) linear molecule.

D) binary molecule.

A

147.

154) A lone pair of electrons

A) occupies a smaller volume than a bonding pair.

B) occupies a larger volume than a bonding pair.

C) occupies the same volume as a bonding pair.

D) will cause the bond angles to be larger.

B

148.

155) Which of the following compounds is **NOT** polar?

  1. A) CBr4
  2. B) CH2F2
  3. C) NF3
  4. D) NH2I



A

149.

156) Which of the following statements about molecules is correct?

A) A compound that contains only nonpolar bonds can be polar.

B) A compound that contains only polar bonds can be nonpolar.

C) A compound that contains only polar bonds must be polar.

D) A compound that contains both polar and nonpolar bonds must be nonpolar.

B

150.

157) Which of the following molecules is polar?

  1. A) O2
  2. B) CCl4
  3. C) CH2Cl2
  4. D) CO2



C

151.

158) All of the following statements about molecular recognition processes are true **EXCEPT**

A) they require smaller amounts of solvents than traditional methods do.

B) they contribute greatly to polluting the environment than traditional methods do.

C) they can be carried out at lower temperatures than traditional methods do.

D) they use less energy than traditional methods do.

B