Deck 4: Molecular Compounds

Question 1

Which of the following structures is likely to exist?

A)

B)

C)

D)

E)None of these may exist.

Answer 1

Question 2

When two atoms share one or more pairs of electrons,a covalent bond is formed.

Answer 2

True

Question 3

A chemical bond formed when two atoms share six electrons is a ________ bond;it is best described as ________.

A)double;covalent
B)double;ionic
C)single;covalent
D)single;ionic
E)triple;covalent

Answer 3

triple;covalent

Question 4

For the dot structure shown the most likely elements are X =________ and Y = ________.

A)carbon;hydrogen
B)carbon;fluorine
C)carbon;oxygen
D)hydrogen;carbon
E)fluorine;carbon

Question 5

For the structure shown,the most likely elements are X = ________ and Y = ________.

A)carbon;oxygen
B)carbon;hydrogen
C)nitrogen;oxygen
D)oxygen;carbon
E)oxygen;hydrogen

Question 6

A chemical bond formed between two identical atoms is a(an)________ bond.

A)atomic
B)covalent
C)hydrogen
D)ionic
E)molecular

Question 7

Which element is most likely to form three covalent bonds?

A)C
B)Si
C)P
D)S
E)Se

Question 8

In a covalent compound,the bond length can be defined as the distance between

A)any two pairs of electrons.
B)the two largest atoms.
C)two nuclei when the repulsion is greatest.
D)two nuclei when the attraction is greatest.
E)two nuclei when repulsion and attraction are balanced.

Question 9

Which element is most likely to make two covalent bonds in the formation of a molecular compound?

A)phosphorus
B)sulfur
C)bromine
D)nitrogen

Question 10

A triple bond involves the sharing of ________ pairs of electrons between the atoms

A)1
B)2
C)3
D)4
E)5

Question 11

When a non-metal atom bonds with another non-metal atom,an ionic bond is formed.

Question 12

The smallest possible unit of a covalent compound is a(an)

A)atom.
B)cation.
C)formula unit.
D)molecule.
E)polyatomic ion.

Question 13

Which group contains only elements which normally exist as diatomic molecules?

A)nitrogen;sulfur,bromine
B)helium;neon,argon
C)nitrogen;oxygen,fluorine
D)hydrogen;lithium,sodium
E)oxygen;phosphorus,germanium

Question 14

A chemical bond formed when two atoms share three pairs of electrons is a ________ bond;it is best described as ________.

A)double;covalent
B)single;covalent
C)triple;covalent
D)double;ionic
E)triple;ionic

Question 15

A chemical bond formed when two atoms share one pair of electrons is a ________ bond;it is best described as ________.

A)double;covalent
B)double;ionic
C)single;covalent
D)single;ionic
E)triple;covalent

Question 16

Which representation of a hydrogen molecule is not correct?

A)H=H
B)H₂
C)H:H
D)H-H
E)none of the above

Question 17

A chemical bond formed when two atoms share two pairs of electrons is a ________ bond;it is best described as ________.

A)double;covalent
B)double;ionic
C)single;covalent
D)single;ionic
E)triple;covalent

Question 18

The covalent bonding model is most useful in describing which of the following compounds?

A)CoCl₂
B)MgCl₂
C)NiCl₂
D)SCl₂
E)none of the above

Question 19

Which group in the Periodic Table is most likely to contain the element X in the molecule whose dot structure is shown?

A)2A
B)3A
C)4A
D)5A
E)6A

Question 20

Which element is most likely to be "X" in the diatomic molecule shown?

A)nitrogen
B)oxygen
C)fluorine
D)hydrogen
E)helium

Question 21

Which representation of a methane molecule is not correct? (A methane molecule is composed of one carbon atom and four hydrogen atoms. )

A)C
B)

C)

D)

E)none of the above

Question 22

What is the molecular geometry of PH₃?

A)linear
B)trigonal planar
C)tetrahedral
D)bent
E)trigonal pyramidal

Question 23

The total number of valence electrons in a molecule of SOF₂ is

A)26.
B)24.
C)18.
D)20.
E)22.

Question 24

Draw the Lewis structure for the a molecule of ethylamine,CH₃CH₂NH_2.

Question 25

Which of the following structures is the correct structure for SOCl₂?

A)

B)

C)

D)

E)

Question 26

In a Lewis dot structure the electrons which complete an octet but are not located between two atoms are referred to as

A)bonding pairs.
B)delta minus electrons.
C)excess electrons.
D)filled shells.
E)lone pairs.

Question 27

The molecule SiCl₄ has a ________ shape.

A)bent
B)linear
C)planar
D)pyramidal
E)tetrahedral

Question 28

The VSEPR model of molecular structure requires a knowledge of ________ to predict the geometry of an atom in a molecule.

A)the number of atoms bonded to the atom of interest
B)the total number of atoms in the molecule
C)the number of electron pairs on the atom of interest
D)both A and C
E)none of the above

Question 29

Explain why it is unlikely that an organic molecule would have an odd number of valence electrons.

Question 30

A molecule in which the central atom forms one double bond and two single bonds is said to have a ________ shape.

A)bent
B)linear
C)trigonal planar
D)pyramidal
E)tetrahedral

Question 31

In forming covalent bonds where the octet rule is obeyed,sulfur usually forms ________ bonds and chlorine usually forms ________ bonds.

A)one;one
B)two;two
C)one;two
D)two;one
E)six;seven

Question 32

Which property is most closely associated with covalent molecules?

A)It is a gas at room temperature.
B)It conducts electricity when dissolved in water.
C)It has a very high melting point.
D)It is composed of a metal and a nonmetal.
E)none of these.

Question 33

Which property could describe a covalent compound?

A)It conducts electricity when melted.
B)It is a gas at room temperature.
C)It is composed of a non-metal and a metal.
D)It conducts electricity when dissolved in water.
E)none of the above

Question 34

The number of valence electrons in the acetic acid molecule (CH₃CO₂H)is

A)0.
B)8.
C)16.
D)24.
E)32.

Question 35

How many double bonds are there in a molecule of SF₂?

A)0
B)1
C)2
D)3
E)4

Question 36

A molecule in which the central atom forms three single bonds and has one lone pair is said to have a ________ shape.

A)bent
B)linear
C)planar
D)pyramidal
E)tetrahedral

Question 37

A molecule in which the central atom has no lone pairs and forms four single bonds is said to have a ________ shape.

A)bent
B)linear
C)planar
D)pyramidal
E)tetrahedral

Question 38

Which set of properties would identify an unknown white solid as a molecular compound?
I.Contains a metal.
II.Has a definite crystal structure.
III.Dissolves in water,but not in organic liquids.
IV.Melts at 80 degrees Celsius.
V.Does not conduct electricity when melted.

A)I,II,III
B)I,III,V
C)II,III,IV
D)II,IV,V
E)I,IV,V

Question 39

Covalent compounds form distinct molecules,and therefore may exist as gases,liquids,or solids at room temperature,depending on the characteristics of the compound.

Question 40

The element least likely to obey the octet rule in forming chemical bonds is

A)boron.
B)carbon.
C)nitrogen.
D)oxygen.
E)fluorine.

Question 41

The bond angle in the molecule H₂S is ________ because the ________.

A)exactly 109.5°;S atom has four charge clouds
B)greater than 109.5°;lone pairs allow the bond angle to expand
C)less than 109.5°;lone pairs force the hydrogen atoms closer together
D)exactly 120°;lone pairs are counted as one charge cloud
E)exactly 180°;the S atom has two bonds

Question 42

Which of the following molecules has a CCH bond angle of 180°?

A)HCCH
B)H₂CCH₂
C)H₃CCH₃
D)H₃CCHO
E)none of them

Question 43

According to VSEPR theory,a molecule with three charge clouds including one lone pair would have a ________ shape.

A)bent
B)linear
C)tetrahedral
D)trigonal planar t
E)pyramidal

Question 44

A section of the Periodic Table containing main group elements is shown.If the elements W,X,Y,and Z have electronegativity values of 1.0,2.0,2.5,and 3.5,respectively,which bond is ionic?

A)WY
B)WZ
C)XY
D)XZ
E)YZ

Question 45

Explain how it is possible for CCl₄ to have polar bonds but be a non-polar molecule.A diagram may be helpful in your answer,but it must be explained.

Question 46

A bond where the electrons are shared equally is called a(an)________ bond.

A)polar covalent
B)coordinate covalent
C)nonpolar covalent
D)ionic
E)none of the above

Question 47

Consider a bent molecule,such as H₂Se,in which the central atom has two lone pairs of electrons.The electronegativities of H and Se are 2.1 and 2.4,respectively.Based on these values and on consideration of molecular geometry,the H-Se bond can be considered almost ________ and the molecule is ________.

A)polar;polar
B)nonpolar;nonpolar
C)polar;nonpolar
D)nonpolar;polar
E)none of the above

Question 48

What is the systematic name of ICl₃?

A)iodine chloride
B)iodine(III)chloride
C)triiodine chloride
D)iodine trichloride
E)tri(iodine chloride)

Question 49

The carbon dioxide molecule is linear.The electronegativities of C and O are 2.5 and 3.5,respectively.Based on these values and on consideration of molecular geometry,the C-O bond is ________ and the molecule is ________.

A)polar;polar
B)nonpolar;nonpolar
C)polar;nonpolar
D)nonpolar;polar
E)none of the above

Question 50

Consider the molecule SiCl₄.The electronegativity values for Si and Cl are 1.8 and 3.0,respectively.Based on these values and on consideration of molecular geometry,the Si-Cl bond is ________ and the molecule is ________.

A)polar;polar
B)nonpolar;nonpolar
C)polar;nonpolar
D)nonpolar;polar
E)none of the above

Question 51

The water molecule has a ________ geometry because its central atom has ________ bonds and ________ lone pairs of electrons.

A)bent;two;two
B)linear;two;two
C)pyramidal;three;one
D)tetrahedral;four;zero
E)planar triangular;three;one

Question 52

A section of the Periodic Table containing main group elements is shown.Which bond would be least polar?

A)WX
B)YZ
C)WZ
D)WY
E)cannot be determined without more specific information

Question 53

Which element listed is the least electronegative?

A)nitrogen
B)hydrogen
C)oxygen
D)fluorine
E)chlorine

Question 54

Based on your knowledge of electronegativities determine whether the bonds between the following pairs of atoms are ionic,polar covalent or nonpolar covalent:

A) F-F
B) Cs-Br
C) N-S

Question 55

Which element listed is the most electronegative?

A)aluminum
B)bromine
C)chlorine
D)iodine
E)sodium

Question 56

Draw the Lewis structure for CCl₄.What is the molecular geometry of this compound? Is the molecule polar or nonpolar?

Question 57

A molecule that contains three identical polar bonds to the central atom will be

A)nonpolar if the geometry is planar triangular.
B)polar in all cases.
C)nonpolar in all cases.
D)impossible to tell the polarity.
E)either polar or nonpolar depending on the identity of the atoms bonded to the central atom.

Question 58

A bond where the electrons are shared unequally is called a(an)________ bond.

A)polar covalent
B)coordinate covalent
C)nonpolar covalent
D)ionic
E)none of the above

Question 59

Which of the following compounds is likely to have ionic bonds between the atoms?

A)CH₄
B)CaCl₂
C)NBr₃
D)SO₂
E)All of these have covalent bonds.

Question 60

A section of the Periodic Table containing main group elements is shown.If the elements W,X,Y,and Z have electronegativity values of 1.0,2.0,2.5,and 3.5,respectively,which bond is the least polar?

A)WX
B)WZ
C)XY
D)XZ
E)YZ

Question 61

Match the following.
bromine pentafluoride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 62

Match the following.
dinitrogen tetroxide

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 63

Match the following.
methane

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 64

Match the following.
sulfur dioxide

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 65

The formula for sulfur hexabromide is

A)SF_6.
B)SBr_6.
C)SBr_4.
D)SiBr_6.
E)SiB_6.

Question 66

Match the following.
carbon tetrachloride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 67

The formula for carbon disulfide is

A)CS_2.
B)C₂S.
C)CSi_2.
D)CaS_2.
E)(CS)_2.

Question 68

Match the following.
carbon monoxide

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 69

Although noble gases do not normally form covalent compounds,XeO₃ has been prepared.The systematic name of this compound is

A)trioxy xenon.
B)trixenon trioxide.
C)xenon trioxide.
D)xenon(III)oxide.
E)none of the above

Question 70

If SiCl₄ is named as a covalent compound,what would it be called?

A)silicon chloride
B)chlorosilicate
C)silicon tetrachloride
D)sulfur chloride
E)sulfur tetrachloride

Question 71

Match the following.
iodine monochloride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 72

The formula for phosphorus pentafluoride is

A)PhF_5.
B)PF_5.
C)P₅F.
D)(PF)_5.
E)P₅F_5.

Question 73

Match the following.
ammonia

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 74

The compound BrF₃ would be called

A)boron trifluoride.
B)triboron fluoride.
C)tri (bromine fluoride).
D)tribromine fluoride.
E)bromine trifluoride.

Question 75

Match the following.
iodine heptafluoride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 76

Match the following.
phosphorus trichloride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 77

Match the following.
oxygen difluoride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I

Question 78

Match the following.
sulfur hexafluoride

A)ICl
B)C
C)N
D)PC
E)
F)CO
G)S
H)S
I)O
J)Br
K)CC
L)I