Deck 3: Chemical Bonds

Question 1

All the following elements exist as diatomic gases at room temperature and atmospheric pressure except

A)H.
B)Ar.
C)N.
D)Cl.
E)O.

Answer 1

Ar.

Question 2

If 491 kJmol^1 is released in the reaction Na⁺(g)+ Cl^(g) Na⁺Cl^(g),what is the energy change for the reaction Na(g)+ Cl(g) Na⁺Cl^(g)? (Hint: See the discussion in the text and apply Hess's Law.)

Answer 2

346 kJmol^1

Question 3

Use the expression for the Coulomb potential energy to calculate the energy for formation of 1 mole of rubidium chloride ion-pairs,that is,the energy change for the following reaction:
Rb⁺(g)+ Cl^(g) Rb⁺Cl^(g)
Use r₁₂ = 330 pm.

Answer 3

421 kJmol^1

Question 4

Which of the following has the highest lattice energy?

A)NaCl
B)KI
C)MgO
D)BaO
E)CaO

Question 5

For the ground-state ion Pb²⁺,what type of orbital do the electrons with highest energy reside in?

A)6p
B)5p
C)4f
D)6s
E)5d

Question 6

Which of the following metal ions has the ground-state electron configuration [Ar]3d⁶?

A)Ni³⁺
B)Fe²⁺
C)Mn²⁺
D)Cu⁺
E)Ca²⁺

Question 7

Predict the electronic configuration in the oxide ion in CaO.

A)[He]2s²2p⁶ or [Ne]
B)[He]2s²2p⁵
C)[He]2s²2p⁶3s²
D)[Ne]3s¹3p³
E)[Ne]3s²3p³

Question 8

An element,E,has the electronic configuration [Ne] 3s²3p¹.Write the formula of its compound with sulfate.

Question 9

Metals rarely lose electrons in chemical reactions because

A)their electron affinities are too high.
B)their ionic radii become too small.
C)their ionization energies are too small.
D)their size is too small.
E)their ionization energies are too high.

Question 10

Which of the following has the highest melting point?

A)KF
B)KI
C)RbF
D)KBr
E)KCl

Question 11

How many lone pairs of electrons are found in the Lewis structure of the interhalogen compound ICl₃?

A)10
B)4
C)8
D)6
E)7

Question 12

Use the expression for the Coulomb potential energy to calculate the energy for formation of 1 mole of sodium chloride ion-pairs,that is,the energy change for the following reaction:
Na⁺(g)+ Cl^(g) Na⁺Cl^(g)
Use r₁₂ = 283 pm.

Question 13

For the ground-state ion Bi³⁺,what type of orbital do the electrons with highest energy reside in?

A)5d
B)6s
C)4f
D)5p
E)6p

Question 14

The Madelung constant is different for all crystals.True or false?

Question 15

Because of the octet rule,the gaseous O^2 ion is stable.True or false?

Question 16

Write the formula of magnesium phosphide.

Question 17

Which of the following has the lowest lattice energy?

A)KCl
B)LiCl
C)KBr
D)NaCl
E)KI

Question 18

For the ground-state ion I^,what type of orbital do the electrons with highest energy reside in?

A)4d
B)6s
C)5p
D)5d
E)5s

Question 19

If 346 kJmol^1 is released in the reaction Na(g)+ Cl(g) Na⁺Cl^(g),is the energy change for the reaction Na⁺Cl^(g) NaCl(s)endothermic or exothermic?

Question 20

For the ground-state ion Sn⁴⁺,what type of orbital do the electrons with highest energy reside in?

A)4p
B)5p
C)4f
D)4d
E)5s

Question 21

How many electrons are in the expanded valence in I₃^?

A)12
B)6
C)10
D)14
E)8

Question 22

Draw the Lewis structure of xenon difluoride and give the number of lone pairs electrons around the central atom.

Question 23

How many lone pairs of electrons are found in the Lewis structure of urea,(NH₂)₂CO?

A)2
B)3
C)6
D)4
E)8

Question 24

In the "best" Lewis structure of XeO₄,there are two double bonds and the formal charge on Xe is zero.True or false?

Question 25

Draw the Lewis structure of the formate ion and indicate whether resonance forms are possible.

Question 26

How many lone pairs of electrons are found in the Lewis structure of hydrazine,H₂NNH₂?

A)8
B)4
C)1
D)0
E)2

Question 27

Predict the N-O bond lengths in NO₂^,given the N-O and N=O bond lengths of 140 and 120 pm,respectively.

Question 28

For dinitrogen monoxide,the arrangement of the atoms is N-N-O.In the Lewis structure with a single bond between NN and a triple bond between NO,the formal charges on N,N,and O,respectively,are

A)(1, +1, 0.)
B)0, 0, 0.
C)0, +1, 1.
D)0, 1, +1.
E)(2, +1, +1.)

Question 29

Why are the N-O bond lengths in NO₃^ the same?

Question 30

Draw the "best" Lewis structures of hydrogen azide,HN₁N₂N₃,and the azide ion,N₁N₂N₃^ .The subscripts are used for identification.For each,match the following bond lengths to the correct N-N bond.The bond lengths can be used more than once.
N-N bond
Bond length,pm
hydrogen azide
N₁-N₂
113
N₂-N₃
116
azide ion
N₁-N₂
124
N₂-N₃

Question 31

How many electrons are in the expanded valence in XeO₄?

Question 32

Consider the following equilibrium:
S₂O₄^2(aq)↔ 2SO₂^(aq)
K ~ 10^9
Write a Lewis structure for each species.

Question 33

How many electrons are in the expanded valence in H₂SO₄?

A)12
B)14
C)8
D)6
E)10

Question 34

Write three Lewis structures for the cyanate ion,NCO^,where the arrangement of atoms is N-C-O.In the most plausible structure,

A)there is a triple bond between N and C.
B)there are two double bonds.
C)there is a triple bond between C and O.
D)the formal charge on O is +1.
E)the formal charge on N is 1.

Question 35

In the most plausible Lewis structure of XeOF₂,there are

A)2 single bonds, 1 double bond, and 1 lone pair of electrons around Xe.
B)3 single bonds and 1 lone pair of electrons around Xe.
C)2 single bonds, 1 double bond, and 3 lone pairs of electrons around Xe.
D)2 single bonds, 1 double bond, and 2 lone pairs of electrons around Xe.
E)3 single bonds and 2 lone pairs of electrons around Xe.

Question 36

Which of the following species are radicals?

A)CO₂
B)HNO₃
C)NO₂
D)NO₃^

Question 37

For dinitrogen monoxide,the arrangement of the atoms is N-N-O.In the Lewis structure with a double bond between NN and NO,the formal charges on N,N,and O,respectively,are

A)0, 1, +1.
B)(1, +1, 0.)
C)0, +1, 1.
D)0, 0, 0.
E)(2, +1, +1.)

Question 38

Which of the following species are radicals?

A)CH₂O
B)HCN
C)HclO
D)ClONO₂
E)ClO

Question 39

Which of the following do not have resonance structures?

A)CH₃CONH^
B)CH₂COCH₃^
C)H₂CO
D)All have resonance structures.

Question 40

How many electrons are in the expanded valence in XeOF₂?

A)14
B)12
C)8
D)10
E)6

Question 41

Estimate the CO bond length in acetone,CH₃COCH₃.Given: covalent radii (pm)of C-,77; C=,67; O-,74; O=,60; H,37.

A)75.5 pm
B)127 pm
C)63.5 pm
D)151 pm
E)137 pm

Question 42

Which of the following compounds contains the weakest bonds to hydrogen?

A)CH₄
B)H₂O
C)SiH₄
D)HF
E)H₂S

Question 43

Use the bond enthalpies given to estimate the heat released when 2-methyl-1-propene,(CH₃)₂C=CH₂,reacts with HBr to give (CH₃)₂CBrCH₃.Bond enthalpies (kJmol^1): C-H,412; C-C,348; C=C,612; C-Br,276; H-Br,366.

A)58 kJmol^1
B)507 kJmol^1
C)317 kJmol^1
D)288 kJmol^1
E)181 kJmol^1

Question 44

If the following all crystallize in the same type of structure,which has the highest lattice energy?

A)LiCl
B)KF
C)KBr
D)KCl
E)LiF

Question 45

Use the bond enthalpies given to estimate the heat released when ethene,CH₂=CH₂,reacts with hydrogen to give CH₃CH₃.Bond enthalpies (kJmol^1): C-H,412; C-C,348; C=C,612; C-Br,276; H-H,436.

A)124 kJmol^1
B)342 kJmol^1
C)288 kJmol^1
D)148 kJmol^1
E)560 kJmol^1

Question 46

Which of the following compounds is the least stable?

A)CH₄
B)SnH₄
C)SiH₄
D)GeH₄
E)PbH₄

Question 47

Write all possible Lewis structures of sulfur dioxide.Which structure is most feasible?

Question 48

Which of the following statements is true?

A)The electronegativity of an atom is defined as electron affinity of the atom.
B)The electronegativity of an atom depends only on the value of the ionization energy of the atom.
C)Atoms with high ionization energies and high electron affinities have low electronegativities.
D)Atoms with low ionization energies and low electron affinities have low electronegativities.
E)Atoms with low ionization energies and low electron affinities have high electronegativities.

Question 49

Use the bond enthalpies given to estimate the heat released when ethene,CH₂=CH₂,reacts with HBr to give CH₃CH₂Br.Bond enthalpies (kJmol^1): C-H,412; C-C,348; C=C,612; C-Br,276; Br-Br,193; H-Br,366.

A)1036 kJmol^1
B)200 kJmol^1
C)470 kJmol^1
D)424 kJmol^1
E)58 kJmol^1

Question 50

If the following all crystallize in the same type of structure,which has the lowest lattice energy?

A)CaO
B)BaS
C)SrO
D)SrS
E)BaO

Question 51

If the following all crystallize in the same type of structure,which has the highest lattice energy?

A)NaCl
B)NaF
C)KF
D)NaBr
E)NaI

Question 52

Which of the compounds below has bonds with the most covalent character?

A)NaCl
B)LiCl
C)CaCl₂
D)BeCl₂
E)MgCl₂

Question 53

Estimate the CN bond length in urea,NH₂CONH₂.Given: covalent radii (pm)of C-,77; C=,67; N-,75; N=,60; O-,74; O=,60; H,37.

A)71 pm
B)127 pm
C)76 pm
D)152 pm
E)142 pm

Question 54

Which of the compounds below has bonds with the most covalent character?

A)CaO
B)Li₂O
C)MgO
D)MgS
E)CaS

Question 55

Which of the following species has bonds with the most ionic character?

A)SiO₂
B)PCl₃
C)P₄O₁₀
D)CO₂
E)NO₂

Question 56

Which of the following statements is true?

A)Atoms with high ionization energies and high electron affinities are highly electronegative.
B)Atoms with high ionization energies and high electron affinities have low electronegativities.
C)The electronegativity of an atom depends only on the value of the ionization energy of the atom.
D)Atoms with low ionization energies and low electron affinities have high electronegativities.
E)The electronegativity of an atom is defined as half the electron affinity of the atom.

Question 57

Which of the following compounds contains the strongest bonds to hydrogen?

A)SiH₄
B)CH₄
C)HF
D)H₂S
E)H₂O

Question 58

Which of the compounds below has bonds with the least covalent character?

A)AgI
B)AgCl
C)AgF
D)AlCl₃
E)BeCl₂

Question 59

Use the bond enthalpies given to estimate the heat released when 1-bromobutene,CH₃CH₂CH=CH₂,reacts with bromine to give CH₃CH₂CHBrCH₂Br.Bond enthalpies (kJmol^1): C-H,412; C-C,348; C=C,612; C-Br,276; Br-Br,193.

A)181 kJmol^1
B)317 kJmol^1
C)288 kJmol^1
D)95 kJmol^1
E)507 kJmol^1

Question 60

Which of the following species has bonds with the most ionic character?

A)CO₂
B)NO₂
C)SnO₂
D)P₄O₁₀
E)PCl₃

Question 61

If the following all crystallize in the same type of structure,which has the lowest lattice energy?

A)LiCl
B)NaI
C)NaCl
D)KCl
E)KI

Question 62

Of the following molecules,which has the strongest bonds?

A)H₂O
B)H₂Se
C)H₂Te
D)H₂S

Question 63

The best Lewis structures of SO₂ and O₃ include expanded valence structures such as O=S=O and O=O=O.True or false?

Question 64

An element E has the electronic configuration 1s²2s²2p⁴.What is the formula of its compound with lithium?

A)LiE₂
B)LiE
C)Li₂E
D)Li₄E

Question 65

Sulfur is more electronegative than oxygen.True or false?

Question 66

Which of the following has resonance structures?

A)XeOF₂
B)N₂H₄
C)CH₃CONH^
D)H₂CO

Question 67

How many valence electrons are present in W⁴⁺?

Question 68

How many resonance structures can be drawn for N₂O?

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

Question 69

The electronegativity of an element can be expressed as ½(I + E_a)where I is the ionization energy and E_a is the electron affinity.True or false?

Question 70

White phosphorus is composed of tetrahedral molecules of P₄ in which every P atom is connected to three other P atoms.In the Lewis structure of P₄,there are

A)3 bonding pairs and 4 lone pairs of electrons.
B)6 bonding pairs and 2 lone pairs of electrons.
C)5 bonding pairs and 4 lone pairs of electrons.
D)6 bonding pairs and no lone pairs of electrons.
E)6 bonding pairs and 4 lone pairs of electrons.

Question 71

White phosphorus is composed of tetrahedral molecules of P₄ in which each P atom is bonded to three others.In this molecule the formal charge on each P atom is ___.

Question 72

Match each of the following compounds with its lattice energy.
KI,LiF,MgF₂,LiI 2961,1046,759,645 kJ/mol

Question 73

How many double bonds are present in the "best" resonance structure of the phosphate ion?

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

Question 74

What is the electronic configuration of Ag?

Question 75

Which of the following is a radical?

A)BrO
B)CH₃⁺
C)CH₃^
D)BF₄^

Question 76

If dinitrogen oxide has a dipole moment,what is the arrangement of atoms?

Question 77

There are three resonance structures of the sulfate ion.A resonance structure can be written where the formal charge on sulfur is 0.True or false?

Question 78

What is the formal charge on the Xe atom in XeF₄?

A)0
B)(4)
C)+2
D)+4

Question 79

How many lone pairs of electrons are there in the Lewis structure of Al₂Cl₆?

A)24
B)12
C)4
D)16

Question 80

What is wrong with the following Lewis structure?

A)The valence electron count
B)The positioning of the carbon atom
C)The distribution of valence electrons
D)The charge on the carbon atom
E)The dipole of the molecule