Deck 4: Molecular Compounds

Question 1

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

Answer 1

double; covalent

Question 2

In a covalent compound the bond length can be defined as

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

Answer 2

the distance between two nuclei when repulsion and attraction are balanced.

Question 3

Which representation of a hydrogen molecule is not correct?

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

Answer 3

H=H

Question 4

The element in the list given that is most likely to form a coordinate covalent bond is

A)H.
B)C.
C)K.
D)Fe.
E)Ca.

Question 5

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 6

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

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

Question 7

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

Question 8

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 9

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 10

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 11

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 12

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

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

Question 13

Which point identifies the bond length between the two atoms of the diatomic molecule whose potential energy is shown on the graph?

Question 14

Which point identifies the maximum repulsion between the two atoms of the diatomic molecule whose potential energy is shown in the graph?

Question 15

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

Question 16

Which element is most likely to form three covalent bonds?

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

Question 17

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

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

Question 18

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 19

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

Question 20

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

A)CH₄
B)

C)

D)

E)none of the above

Question 21

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 22

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 23

What is the molecular geometry of PH₃?

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

Question 24

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 25

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 26

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 27

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 28

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

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

Question 29

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

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

Question 30

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

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

Question 31

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 32

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 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 molecule SiCl₄ has a ________ shape.

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

Question 35

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

Question 36

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 37

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 38

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 39

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

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

Question 40

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 41

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 42

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 43

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 44

The VSEPR model or 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 45

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 46

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 47

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

Question 48

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 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

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 51

The formula for sulfur hexabromide is ________.

A)SF₆
B)SBr₆
C)SBr₄
D)SiBr₆
E)SiB₆

Question 52

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 53

Which element listed is the least electronegative?

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

Question 54

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 55

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 56

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 57

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 58

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 59

Which element listed is the most electronegative?

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

Question 60

The formula for phosphorus pentafluoride is ________.

A)PhF₅
B)PF₅
C)P₅F
D)(PF)₅
E)P₅F₅

Question 61

Match the following.
dinitrogen tetroxide

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 62

The compound BrF₃ would be called

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

Question 63

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 64

Match the following.
sulfur dioxide

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 65

Match the following.
carbon monoxide

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 66

Match the following.
phosphorus trichloride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 67

Match the following.
carbon tetrachloride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 68

Match the following.
iodine heptafluoride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 69

Match the following.
methane

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 70

Match the following.
bromine pentafluoride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 71

Match the following.
ammonia

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 72

Match the following.
oxygen difluoride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 73

Match the following.
iodine monochloride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃

Question 74

The formula for carbon disulfide is ________.

A)CS₂
B)C₂S
C)CSi₂
D)CaS₂
E)(CS)₂

Question 75

Match the following.
sulfur hexafluoride

A)OF₂
B)BrF₅
C)CCI₄
D)N₂O₄
E)SF₆
F)CO
G)ICl
H)SO₂
I)CH₄
J)IF₇
K)PCI₃
L)NH₃