Chemistry Chapter 9 Answers – Flashcards
Flashcard maker : Aiden Simmons
In which pair do both compounds exhibit predominantly ionic bonding?
RbCl and CaO
The following representation of an atom is called
A Lewis dot structure
Which of the following concerning Coulomb’s law is/are correct?
1. The energy of an ionic bond is proportional to the size of the ion charges
2. The energy of an ionic bond is inversely proportional to the distance between the charges
3. The size of an ion is not important in determining the energy of an ionic bond
1. The energy of an ionic bond is proportional to the size of the ion charges
2. The energy of an ionic bond is inversely proportional to the distance between the charges
3. The size of an ion is not important in determining the energy of an ionic bond
1 & 2
When the action Na⁺, K⁺, Rb⁺, Cs⁺ are combined with chloride ion in the gas phase to form ion pairs, which pair formation releases the greatest amount of energy?
NaCl
Which one of the following has an enthalpy change that is equal to the lattice energy of CaF₂?
CaF₂(s) —> Ca²⁺(g) + 2F⁻(g)
Which of the following statements concerning lattice energy is false?
The lattice energy for a solid with 2+ and 2- ions should be two times that for a solid with 1+ and 1- ions
Which of the following is a correct description of lattice energy?
The energy change that occurs when an ionic solid is separated into its ions in the gas phase
In the Born-Haber cycle for NaBr(s), which of the following processes corresponds to the first ionization energy of Na?
Na(g) –> Na⁺(g) + e⁻
In the Born-Haber cycle for KBr(s), which of the following processes corresponds to the enthalpy of formation of KBr(s)?
K(s) + 1/2Br₂(l) —> KBr(s)
In the Born-Haber cycle for KF(s), which of the following processes corresponds to the electron affinity of F?
F(g) + e⁻—> F⁻(g)
Which of the following processes is not exothermic?
1/2Br₂(g) —> Br(g)
Calculate the lattice energy for LiF(s) given the following:
sublimation energy for Li(s) +166 kJ/mol
∆Hf for F(g) +77kJ/mol
first ionization energy of Li(g) +520. kJ/mol
electron affinity of F(g) -328 kJ/mol
enthalpy of formation of LiF(s) -617 kJ/mol
sublimation energy for Li(s) +166 kJ/mol
∆Hf for F(g) +77kJ/mol
first ionization energy of Li(g) +520. kJ/mol
electron affinity of F(g) -328 kJ/mol
enthalpy of formation of LiF(s) -617 kJ/mol
1052 kJ/mol
Which of the following compounds has the most ionic bonding (has the highest percentage of ionic character)
CsF
Which of the following compounds would be expected to have the lowest melting point?
RbF
Which of the following compounds would be expected to have the highest melting point?
A. CsF
B. LiCl
C. LiF
D. NaBr
E. CsI
A. CsF
B. LiCl
C. LiF
D. NaBr
E. CsI
LiF
Which of the following compounds would be expected to have the highest melting point?
A. NCl₃
B. OCl₂
C. MgCl₂
D. CCl₄
A. NCl₃
B. OCl₂
C. MgCl₂
D. CCl₄
MgCl₂
Atoms of an element X have the ground-state electron configuration 1s²2s²2p⁶3s²3p⁴. What type of ion is X most likely to form?
X²⁻
Which of the following is the Lewis dot structure for the rubidium ion?
E. Rb⁺
Which of the following is the Lewis dot structure for the bromide ion?
E. Br⁻ with dots all around
Which of the following is the Lewis dot structure for one formula unit of magnesium sulfide?
A. Mg²⁺ S²⁻ with dots all around
All of the following species have ground-state noble-gas electron configurations except?
Ge⁴⁺
Which of the following concerning the formation of ions is/are correct?
1. Elements with large electron affinities tend to form monoatomic anions
2. No ionic compounds are found with positive ions having charges greater than the element group number
3. Group 1A and 2A metals always have a positive charge equal to their group number in their ionic compounds.
1. Elements with large electron affinities tend to form monoatomic anions
2. No ionic compounds are found with positive ions having charges greater than the element group number
3. Group 1A and 2A metals always have a positive charge equal to their group number in their ionic compounds.
1,2,&3
Which of the following concerning the formation of ions is/are correct?
1. Compounds of +4 ions are rare because of the large amount of energy required to form a +4 ion.
2. Some main group metals may have more than one possible positive charge because of the different energies required to remove s versus p valence electrons.
3. The nonmetals closest to the noble gases (Group 6A and 7A) tend to form monatomic anions with noble gas configurations.
1. Compounds of +4 ions are rare because of the large amount of energy required to form a +4 ion.
2. Some main group metals may have more than one possible positive charge because of the different energies required to remove s versus p valence electrons.
3. The nonmetals closest to the noble gases (Group 6A and 7A) tend to form monatomic anions with noble gas configurations.
1,2&3
All of the following have ground-state noble-gas configurations except
P³⁺
The formation of which monatomic ion of sulfur is the most energetically favorable?
S²⁻
What is the ground-state electron configuration of the Al³⁺ ion?
1s²2s²2p⁶
What is the ground-state electron configuration of the sulfide ion?
1s²2s²2p⁶3s²3p⁶
What is the electron configuration for Mn³⁺?
[Ar]3d⁴
The Cr²⁺ ion would be expected to have __ unpaired electrons?
4
What is the electron configuration of Mn²⁺?
[Ar]3d⁵
What is the ground-state electron configuration of Co³⁺?
[Ar]3d⁶
What is the ground-state electron configuration of V²⁺?
[Ar]3d³
What is the ground-state electron configuration of the copper(I) ion, Cu⁺?
1s²2s²2p⁶3s²3p⁶3d¹⁰
What is the ground-state electron configuration of Fe³⁺?
[Ar]3d⁵
All of the following ions have the ground-state electron configuration of a noble gas except which one?
Ga³⁺
Which set of ions are isoelectronic in their ground-state electron configurations?
N³⁻, O²⁻, Mg²⁺, Al³⁺
Which of the following species is isoelectronic with Kr?
Sr²⁺
All of the following species are isoelectronic except?
1. Ar
2. Cr²⁺
3. Mg²⁺
4.Cl⁻
5. S²⁻
1. Ar
2. Cr²⁺
3. Mg²⁺
4.Cl⁻
5. S²⁻
Mg²⁺
Which pair of species is isoelectronic?
K⁺ and Cl⁻
Which two species are isoelectronic?
Al³⁺ and Ne
All of the following species are isoelectronic except?
A. S²⁻
B. K⁺
C. Na⁺
D. Ar
E. Cl⁻
A. S²⁻
B. K⁺
C. Na⁺
D. Ar
E. Cl⁻
Na+
All of the following species are isoelectronic except?
A. O⁻
B. Ne
C. N³⁻
D. Mg²⁺
E. F⁻
A. O⁻
B. Ne
C. N³⁻
D. Mg²⁺
E. F⁻
O⁻
The following species, ³¹₁₅P³⁻, ³⁷₁₇Cl⁻, and ⁴⁰₂₀Ca²⁺, all have the same number of?
Electrons
Rank the following ions in order of decreasing atomic radii: Mo⁴⁺, Mo⁵⁺, Mo⁶⁺
Mo4⁺>Mo⁵⁺>Mo⁶⁺
Rank the following ions in order of decreasing atomic radii: Te²⁻, Te⁴⁺, Te⁶⁺
Te²⁻>Te⁴⁺,Te⁶⁺
Which of the following species would you expect to have the largest radius?
Se²⁻
In which of the following lists do the ions NOT appear in order of increasing ionic radius?
S²⁻
Rank the following ions in order of decreasing ionic radius: S²⁻,O²⁻,F⁻,Na⁺,Mg²⁺
S²⁻,O²⁻,F⁻,Na⁺,Mg²⁺
Rank the following species in order of decreasing radii: K⁺,Cl⁻,Se²⁻,Br⁻
Se²⁻>Br⁻>Cl⁻>K⁺
For which of the following pairs of species is the difference in the radius the greatest?
Li⁺ and I⁻
Which of the following is the best explanation for a covalent bond?
Electrons simultaneously attracted by more than one nucleus
The formulas of many binary covalent compounds can be predicted on the basis
That the number of bonds an atom can have is equal to the number of half-filled valence orbitals it can have
During the formation of a chemical bond between two hydrogen atoms, which of the following statements is always true?
Energy is released during the formation of the bond
A bond in which both electrons of the bond are donated by one atom is called __?
A coordinate covalent bond
A bond in which a pair an electron pair is unequally shared by two atoms is
Polar covalent
The measure of the attraction that an atom has for the electrons in a chemical bond is called?
Electronegativity
Which of the following atoms is the most electronegative?
N
An atom of which of the following elements has the highest electronegativity?
Br
Which of the following concerning electronegativity is/are correct?
1. Differences in element electronegativities may be used to predict the type of bonding, ionic or covalent, in a substance
2. The larger the difference in electronegativity between two bonded atoms the more polar the bond
3. The electrons in a polar bond tend to spend more time around the least electronegative element.
1. Differences in element electronegativities may be used to predict the type of bonding, ionic or covalent, in a substance
2. The larger the difference in electronegativity between two bonded atoms the more polar the bond
3. The electrons in a polar bond tend to spend more time around the least electronegative element.
1 and 2
Which pair of elements would form a covalent bond that is the least polar?
O and F
Rank the following covalent bonds in order of decreasing polarity: C-H, N-H, O-H, F-H
F-H, O-H, N-H, C-H
Which of the following bonds would be the least polar yet still be considered polar covalent?
N-O
In which of the following species is there the greatest unequal sharing of the bonding electrons?
H₂O
The Lewis formula for phosphine, PH₃ has?
Three bonding pairs and one lone pair
Which of the following concerning Lewis electron-dot formulae is/are correct?
1. A Lewis electron-dot formula is identical to a structural formula
2. The skeleton of a molecule need not be known to draw the correct Lewis electron-dot structure
3. Lewis electron-dot formulae show the location of bonding and nonbonding electrons in three dimensional space.
1. A Lewis electron-dot formula is identical to a structural formula
2. The skeleton of a molecule need not be known to draw the correct Lewis electron-dot structure
3. Lewis electron-dot formulae show the location of bonding and nonbonding electrons in three dimensional space.
None of the above
What is the total number of valence electrons in N₂O₄?
34
In the Lewis formula for difluorodiazine, N₂F₂, the total number of lone electron pairs around the two nitrogen atoms is?
2
Which of the following Lewis formulas is incorrect?
B- N N
Which of the following is a correct Lewis electron dot formula for H₂SO₄?
A. S in the middle with 2 H’s on the bottom and right side
Which fo the following is a correct Lewis electron-dot formula for CO?
A. 2 dots next to C triple bonded to O with 2 dots
Which one of the following has a Lewis formula most similar to that of NO⁻?
O₂
The Lewis structure for each of the following except __ contains at least one double bond
NO⁺
The Lewis structure for each of the following species except __ contains a triple bond
N₃⁻
How many valence electrons are present in the Lewis formula for the hypochlorite ion, ClO⁻?
14
What is the total number of valence electrons in the azide ion, N₃⁻
16
What is the total number of valence electrons in the nitrosyl ion, NO⁺?
10
How many valence electrons are there in the tetraethylammonium ion, (C₂H₅)₄N⁺?
56
What is the total number of valence electrons in the mono hydrogen phosphate ion, HPO₄²⁻?
32
How many valence electrons does a nitrate ion have?
24
How many valence electrons are there in the acetate ion, CH₃COO⁻?
24
The total number of valence electrons in the peroxide ion, O₂²⁻ is?
14
The number of valence electrons in the perfluoropropionate ion, CF₃CF₂COO⁻ is?
60
The total number of valence electrons in the tetrathionate ion, S₄O₆²⁻ is?
62
The number of valence electrons in the nitrite ion is?
18
The total number of valence electrons in the phosphate ion is?
32
What is the total number of valence electrons in the sulfite ion?
26
In the Lewis formula for hydrazitnium ion, N₂H₅⁺, the total number of lone electron pairs around the two nitrogen atoms is?
1
In the Lewis formula for the hydroxide ion, OH⁻, the number of lone pairs of electrons around the oxygen atom is?
3
The concept of resonance describes molecular structures?
That have delocalized bonding
All the following statements about resonance are true except?
Resonance describes the oscillation and vibration of electrons
Which of the following species is resonance most likely to take place?
A. N double bonded to O at the top and then single bonded to O twice at the bottom
For the resonance hybrid of the nitrite ion, what is the average number of bonds between the nitrogen atom and an oxygen atom?
3/2
Which of the following species is best described by writing 3 equivalent Lewis formulas?
SO₃
For each of the following species except __, the electronic structure may be adequately described by 2 resonance formulas.
SO₃²⁻
Which of the following are 2 appropriate resonance formulas for the acetate ion CH₃CO₂⁻
A
The electronic structure of which of the following species cannot be adequately described by a single Lewis formula?
NO₃⁻
Which of the following species represents an exception to the octet rule?
A. SiO₂
B. HBr
C. SF₄
D. PCl₃
E. CO₂
A. SiO₂
B. HBr
C. SF₄
D. PCl₃
E. CO₂
SF₄
The Lewis structure of a molecule has a high probability of violating the octet rule if
1. The molecule has an odd number of valence electrons
2. The central atom is surrounded by more than four atoms or eight valence electrons
3. The central atom is from Group 2A or 3A
1. The molecule has an odd number of valence electrons
2. The central atom is surrounded by more than four atoms or eight valence electrons
3. The central atom is from Group 2A or 3A
1,2, and 3
In which of the following molecules is the octet rule violated?
SF₆
The octet rule is violated by at least one atom in all of the following compounds except?
SiF₄
The Lewis formula of which species does NOT represent an exception to the octet rule?
CF₃⁻
Which species has the largest number of lone pairs of electrons around the central atom?
XeF₂
In the Lewis formula for ClF₃, how many lone pairs are around the central atom?
2
Which of the following molecules has an incorrect Lewis formula?
A. the structure with the FS molecule
In the Lewis dot formula for Icl₂⁻, the number of lone pairs of electrons around the central iodine atom is?
3
Which of the following has an incomplete octet in its Lewis structure?
NO₂
Which of the following Lewis structures best describes BF₃?
C
Which of the following species represents an exception to the octet rule?
A. BF₃
B. BF₄⁻
C. CH₃OH
D. CCl₄
E. PH₃
A. BF₃
B. BF₄⁻
C. CH₃OH
D. CCl₄
E. PH₃
BF₃
From a consideration of the Lewis structure of the thiocyanate ion, SCN⁻, in which carbon has a double bond with both the sulfur and nitrogen atoms, the formal charges on the sulfur, carbon, and nitrogen atoms are, respectively,?
0,0,-1
Which of the following is/are true concerning formal charge?
1. The formal charge of each individual atom in a molecule or ion is an actual atomic charge that can be experimentally determined.
2. The formal charge of each individual atom is always the same for each possible resonance form
3. The sum of the formal charges of each atom in a molecule or ion equal the overall charge of the molecule or ion
1. The formal charge of each individual atom in a molecule or ion is an actual atomic charge that can be experimentally determined.
2. The formal charge of each individual atom is always the same for each possible resonance form
3. The sum of the formal charges of each atom in a molecule or ion equal the overall charge of the molecule or ion
3 only
In the Lewis formula that minimizes the formal charge, what is the formal charge on the sulfur atom in sulfur trioxide, SO₃?
+2
Which of the following statements is true concerning the Lewis formula that minimizes formal charge for H₂SO₄?
The formal charge of S is 0, the formal charge of O is 0, and the formal charge of H is 0
In which of the following species is the octet rule violated by the central atom when the central atom has a formal charge of zero?
SOCl²
What is the correct Lewis dot formula for sulfuric acid, H₂SO₄, that minimizes formal charge
B- a double bond between O on both top and bottom of S
What is the formal charge on the chlorine atom in the chlorate ion, ClO₃⁻, in the Lewis dot formula that minimizes formal charge?
In the Lewis dot formula that minimizes formal charge, how many bonds are there in the tetrathionate ion, S₄O₆²⁻?
13
In the Lewis dot formula for the bromate ion (BrO₃⁻) that minimizes formal charge, the central atom is surrounded by?
Five bonding pair and one lone pair of electrons
Which Lewis dot formula for pyrophosphate, P₂O₇⁴⁻, minimizes formal charge?
A
As the number of bonds between two carbon atoms increase, which of the following decrease(s)?
only the bond length
Which of the following statements is true?
The triple bond in N₂ has a larger bond order and a smaller bond length than the single bond in F₂
Which of the following species has the shortest bond distance?
H₂
Which of the following diatomic species do you expect to have the longest bond length?
O₂²⁻
Which of the following diatomic molecules has the greatest bond energy?
CO
Consider the reaction 2HCl(g) –> H₂(g) + Cl₂(g); ∆H= 185 kJ
Which of the following statements is false?
The HCl bond is longer than either the H₂ bond or the Cl₂ bond
Using bond-energy data, what is ∆H for the following reaction?
CH₄(g) + 2Cl₂(g) –> CCl₄(g) + 2H₂(g)
CH₄(g) + 2Cl₂(g) –> CCl₄(g) + 2H₂(g)
-40 kJ
Using bond-energy data, what is ∆H for the following reaction?
CH₃OH(g) + H₂S(g) –> CH₃SH(g) + H₂O (g)
CH₃OH(g) + H₂S(g) –> CH₃SH(g) + H₂O (g)
-25 kJ
Based on the following data, what is the Br-Br bond energy?
1/2H₂(g) + 1/2Br₂(g) –> HBr(g); ∆H= -36.44 kJ
1/2H₂(g) + 1/2Br₂(g) –> HBr(g); ∆H= -36.44 kJ
216 kJ/mol
Based on the following data, what is the bond energy of the C=C bond in 1,1-difluoroethylene, CF₂CH₂?
CH₄(g) –> C(g) + 4H(g); ∆H= 1656 kJ
CF₄(g) –> C(g) + 4F(g); ∆H= 1756 kJ
CF₂CH₂(g) –> 2C(g) + 2H(g) + 2F(g); ∆H= 2317kH
CH₄(g) –> C(g) + 4H(g); ∆H= 1656 kJ
CF₄(g) –> C(g) + 4F(g); ∆H= 1756 kJ
CF₂CH₂(g) –> 2C(g) + 2H(g) + 2F(g); ∆H= 2317kH
611 kJ/mol
Which of the following covalent molecules does NOT have the proper Lewis dot formula
B. the formula with C,O,H
Use the bond energies provided to complete the following statement.
____ when all of the bonds in acetic acid (CH₃COOH) are broken
____ when all of the bonds in acetic acid (CH₃COOH) are broken
3153 kJ/mol of energy is consumed
