Deck 4: Covalent Compounds

Question 1

Which of the statements concerning chemical bonds is false?

A)The sharing of electrons between two nonmetal atoms results in a covalent bond.
B)The attraction between oppositely charged ions results in an ionic bond.
C)The term nonpolar is used to describe a covalent bond in which electrons are not shared equally.
D)A bond dipole is the separation of charge that results when atoms sharing electrons have different electronegativities.

Answer 1

The term nonpolar is used to describe a covalent bond in which electrons are not shared equally.

Question 2

How many covalent bonds are generally formed by an oxygen atom?

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

Answer 2

2

Question 3

How many nonbonded electron pairs are in the Lewis structure below?

A)2
B)4
C)6
D)8
E)16

Answer 3

4

Question 4

Which of the following compounds is not classified as covalent?

A)CH₄
B)SF₆
C)PBr₃
D)MgCl₂
E)None of the choices are correct.

Question 5

What is the Lewis structure for chloroethylene (C₂H₃Cl)?

A)
B)
C)
D)

Question 6

Predict the bond angles around the carbon atom in the structure of carbonic acid shown below. Don't forget to draw in lone pairs where needed to give octets.

A)180°
B)120°
C)109.5°
D)90°
E)60°

Question 7

Covalent bonds result from the ________ electrons between two atoms.

A)transfer of
B)equal sharing of
C)unequal sharing of
D)Transfer of,equal sharing of,and unequal sharing of are correct.
E)Equal sharing of and unequal sharing of are correct.

Question 8

How many covalent bonds are generally formed by atoms with five valence electrons?

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

Question 9

Identify the diatomic element from the given choices.

A)Phosphorus
B)Helium
C)Nitrogen
D)Silicon
E)Sodium

Question 10

How many valence electrons are in a molecule of formaldehyde (CH₂O)?

A)16
B)12
C)10
D)8
E)0

Question 11

Which choice would be named carbon tetrachloride?

A)CCl
B)C₄Cl
C)CCl₄
D)CCl₃
E)C₃Cl

Question 12

How many lone pairs of electrons are present in the Lewis structure of ammonia,NH₃?

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

Question 13

What is another name for an unshared pair of electrons in a covalent compound?

A)Lone pair of electrons
B)Nonbonded electron pair
C)Bonding pair of electrons
D)Lone pair of electrons or nonbonded electron pair

Question 14

Identify the diatomic element from the given choices.

A)Chlorine
B)Carbon
C)Boron
D)Sulfur
E)Lithium

Question 15

What is the molecular shape around the phosphorus atom in PH₃?

A)Linear
B)Bent
C)Trigonal planar
D)Tetrahedral
E)Trigonal pyramidal

Question 16

Which choice would be named dinitrogen pentoxide?

A)N₂O₅
B)N₅O₂
C)N₃O₂
D)N₂O₃
E)NO

Question 17

A diatomic molecule contains ________. I. atoms of two different elements bonded together with a covalent bond
II. two atoms of the same element bonded together with a covalent bond
III. two lone pairs of electrons

A)I only
B)II only
C)III only
D)I or II only
E)I and III only

Question 18

Which of the following compounds is classified as covalent?

A)KCl
B)LiBr
C)HCl
D)NaBr
E)None of the choices are correct.

Question 19

Which of the following elements will generally form only one covalent bond?

A)Sulfur
B)Carbon
C)Hydrogen
D)Argon
E)Nitrogen

Question 20

Identify the correct name for the compound NO₂.

A)Nitrogen oxide
B)Dinitrogen monoxide
C)Nitrogen dioxide
D)Nitrogen oxate
E)Nitrate

Question 21

What are the bond angles in a tetrahedral geometry?

A)180°
B)120°
C)109.5°
D)90°
E)60°

Question 22

Which molecule's Lewis structure contains an atom that violates the octet rule?

A)H₂O
B)BeH₂
C)PCl₃
D)H₂Se

Question 23

Estimate the bond angles around the sulfur atom in the structure shown below.

A)90°
B)109.5°
C)120°
D)180°

Question 24

Which molecule or ion has ONLY two resonance structures to describe its bonding?

A)CO₃^2-
B)NO₃^-
C)HCO₃^1-
D)SO₃

Question 25

Which atom has the lowest electronegativity?

A)Al
B)S
C)Se
D)Rb
E)F

Question 26

Which bond is the MOST polar?

A)C-N
B)C-O
C)C-C
D)C-Cl
E)C-F

Question 27

Which element may have more than eight valence electrons around it when present in a covalent compound?

A)C
B)B
C)N
D)P
E)O

Question 28

What is the correct chemical formula of selenium dioxide?

A)SO₂
B)SeO₂
C)Se₂O
D)OS₂

Question 29

Which of the following molecule(s)is(are)polar?

A)CO₂
B)CH₄
C)CBr₄
D)CHBr₃
E)More than one of the molecules are polar.

Question 30

Which bond is the LEAST polar?

A)C-N
B)C-O
C)C-C
D)C-Cl
E)C-F

Question 31

Aspartic acid is an amino acid used to synthesize proteins. How many polar bonds are in the aspartic acid structure shown below?

A)4
B)6
C)9
D)12
E)15

Question 32

Which of the following is classified as a group in the valence shell electron pair repulsion (VSEPR)theory?

A)An atom
B)A lone pair of electrons
C)A valence electron
D)Either an atom or a valence electron
E)Either an atom or a lone pair of electrons

Question 33

What is the molecular shape around the nitrogen atom in the structure shown below?

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

Question 34

Which is the correct Lewis structure for OBr^-?

A)
B)
C)
D)
E)

Question 35

What is the chemical formula for dinitrogen tetroxide?

A)N₄O₂
B)O₄N₂
C)N₂O₄
D)O₂N₄
E)NO₂

Question 36

Rank the atoms Br,Cl,and K in order of increasing electronegativity.

A)K < Br < Cl
B)Cl < Br < K
C)Br < Cl < K
D)K < Cl < Br
E)Cl < K < Br

Question 37

Which bond has the polarity incorrectly labeled?

A).^δ+ H-Cl ^δ-
B).^δ+ O-C ^δ-
C).^δ+ Cl-F ^δ-
D).^δ- Cl-Br ^δ+
E).^δ- F-O ^δ+

Question 38

Rank the atoms Br,Cl,and F in order of increasing electronegativity.

A)F < Br < Cl
B)Cl < Br < F
C)Br < Cl < F
D)F < Cl < Br
E)Cl < F < Br

Question 39

What is the molecular shape around the oxygen atom in the structure shown below?

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

Question 40

Aspartic acid is an amino acid used to synthesize proteins. How many lone pairs of electrons need to be added to complete the aspartic acid structure shown below?

A)4
B)6
C)8
D)9
E)11

Question 41

Which Lewis structure is incorrect?

A)
B)
C)
D)

Question 42

Considering the electronegativity values indicated for each element,which covalent bond has the LEAST degree of polarity?

A)C-N
B)N-O
C)F-F
D)H-Cl

Question 43

How many total valence electrons does the polyatomic ion NH₄⁺ possess?

A)8
B)9
C)10
D)11
E)7

Question 44

Phosphorus usually forms two covalent bonds in a molecule.

Question 45

Atoms with three valence electrons generally form five bonds.

Question 46

Which of the statements concerning compounds is INCORRECT?

A)Compounds are formed when atoms of two or more different elements are chemically bonded.
B)Ionic compounds are composed of cations and anions.
C)Covalent compounds are composed of metals and nonmetals.
D)Covalent compounds are composed of individual molecules.

Question 47

How many lone pairs of electrons need to be added to the Lewis structure of carbonic acid shown below?

A)0
B)3
C)4
D)6
E)7

Question 48

The covalent bond between chlorine and iodine is a polar one. Which of the following properly represents the direction of polarity in this bond?

A).^δ+ Cl-I ^δ-
B).^δ- Cl-I ^δ+
C).⁺ Cl-I ^-
D).^- Cl-I ⁺

Question 49

What is the total number of bonding electrons in the structure below?

A)5
B)10
C)20
D)30

Question 50

Which statement concerning chemical bonds is FALSE?

A)A covalent bond involves the sharing of electrons between two nonmetal atoms.
B)An ionic bond is the attraction between oppositely charged ions.
C)A nonpolar bond is a covalent bond in which electrons are not shared equally between the atoms.
D)Electronegativity is a measure of the attraction an atom has for the electrons it shares in a bond.

Question 51

Which atom(s)in the structure below has(have)a partial negative charge (δ^-)?

A)Carbon
B)Fluorine
C)Hydrogen
D)Nitrogen
E)Nitrogen and fluorine

Question 52

Bonding is the joining of two atoms in a stable arrangement.

Question 53

A Lewis structure shows the connectivity between atoms in a molecule,as well as where all the bonding and nonbonding valence electrons reside.

Question 54

Which compound has the greatest number of valence electrons?

A)H₂S
B)CH₄
C)NH₃
D)H₂O
E)All of the molecules have the same number of valence electrons.

Question 55

A molecule is a discrete group of atoms held together by covalent bonds.

Question 56

How many total valence electrons does the polyatomic ion OBr^- possess?

A)11
B)12
C)13
D)14
E)15

Question 57

Atoms with seven valence electrons typically form one covalent bond.

Question 58

The Lewis structure of formaldehyde is shown below. Which statement concerning this structure is INCORRECT?

A)Two electrons are being shared between the carbon atom and the oxygen atom.
B)The oxygen atom has four valence electrons that are not being shared with another atom.
C)The oxygen and carbon atoms each have an octet of electrons in their valence shells.
D)The hydrogen atoms have filled valence shells.

Question 59

Every atom must have an octet of electrons in order for a Lewis structure to be considered valid.

Question 60

The Lewis structure shown below is not a valid Lewis structure. What statement best describes the error in the structure?

A)The nitrogen atoms violate the octet rule.
B)The chlorine atoms violate the octet rule.
C)The structure contains an incorrect number of valence electrons.
D)Chlorine atoms and nitrogen atoms do not typically form bonds with each other.

Question 61

The formula for dinitrogen pentoxide is N₅O₂.

Question 62

In the valence shell electron pair repulsion (VSEPR)theory,a group is defined as an atom or a lone pair of electrons.

Question 63

The Lewis structure for BH₃ contains an atom that does not follow the octet rule.

Question 64

The symbol δ^- is given to the more electronegative atom in a polar bond.

Question 65

Ethane (C₂H₆)is a polar molecule.

Question 66

Some covalent compounds are solids,some are liquids,and some are gases at room temperature.

Question 67

A bond formed between the elements hydrogen and bromine would be considered an ionic bond.

Question 68

Unequal sharing of electrons in a covalent bond results in a polar bond.

Question 69

A molecule that contains only one polar bond is a polar molecule.

Question 70

A resonance hybrid is a composite of all resonance structures that spreads out electron pairs in multiple bonds and lone pairs.

Question 71

Resonance structures for a substance differ only in the location of multiple bonds and the position of lone electron pairs.

Question 72

The Lewis structure for PH₃ contains an atom that does not follow the octet rule.

Question 73

The structures shown below are resonance structures of sulfur dioxide. and

Question 74

C-H bonds are considered to be nonpolar,because the electronegativity difference between carbon and hydrogen is small.

Question 75

A bond between a carbon atom and a nitrogen atom is a polar covalent bond.

Question 76

A double bond consists of four electrons shared between two atoms.

Question 77

Nonpolar molecules may contain polar bonds.

Question 78

The correct name for SF₆ is sulfur heptafluoride.

Question 79

The structures shown below are resonance structures of sulfur dioxide. and

Question 80

There can be a no more than two resonance structures for a molecule.