Question 1

Where would you expect Ne to appear in the following sequence of boiling points?
He 2 2 2 2

Accepted Answer

A)   lower than He
B)   between He and H2
C)   between H2 and N2
D)   between F2 and Ar
E)   between Ar and O2F) B) and C)
G) A) and E)

Question 2

List the following three compounds in order of increasing boiling point:

Accepted Answer

A)   1, 2, 3
B)   3, 2, 1
C)   1, 3, 2
D)   2, 1, 3
E)   2, 3, 1F) A) and E)
G) B) and E)

Question 3

How much energy is required when 23 grams of ethanol at 30˚C are vapourized from a "flaming" desert? ΔH˚vap = 39.3 kJ/mol, Tvap = 351 K, ΔH˚fus = 7.61 kJ/mol, Tfus = 156 K, Cethanol = 112 J/mol˚C

Accepted Answer

Question 4

Define supercritical fluid and how to make such a fluid.

Accepted Answer

A supercritical fluid is one t...

Question 5

Use the phase diagram of oxygen to estimate the temperature at which liquid oxygen will boil under 0.5 atm external pressure and compare that to the normal boiling point.

Accepted Answer

The answer of Use the phase diagram of oxygen to...

Question 6

Which is the most realistic picture for a container of Ar(l) ?

Accepted Answer

A)        
B)    
C)    
D)   
E)    F) B) and D)
G) All of the above

Question 7

In which of the following pure substances will hydrogen bonding be an important intermolecular force? 1)  dichloromethane, CH2Cl2, 2)  CH3CH2OH, 3)  methylamine, (CH3NH2) , 4)  trimethylamine, N(CH3) 3

Accepted Answer

A)   2 and 3
B)   all
C)   none
D)   1 and 2
E)   3 and 4F) C) and E)
G) B) and D)

Question 8

Of the following pairs, select the pair that undergoes hydrogen bonding and draw a molecular picture of the hydrogen bond interaction.
1. NaCl and acetone, (CH3)2CO
2. CH3OCH3 and CF3Cl
3. NH3 and CCl4
4. NF3 and CF4
5. CH3NH2 and CH3OCH3

Accepted Answer

#5 undergo...

Question 9

30 In the simple cubic crystal structure at right, the unit cell is outlined in heavy lines which intersect to form the corners at the center of the spheres. If the corners of the unit cells are at the center of the spheres, how many atoms are in one unit cell?

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   6F) C) and D)
G) D) and E)

Question 10

Which of the following experience the strongest intermolecular forces?

Accepted Answer

A)   F2
B)   I2
C)   Br2
D)   Cl2E) A) and D)
F) C) and D)

Question 11

Polonium metal crystallizes in a simple cubic structure. If the atomic radius of polonium is 160 pm, what is the volume of a unit cell?

Accepted Answer

A)   3.28x10-23 cm3
B)   4.10 x 10-29 m3
C)   4.10 x106 pm3
D)   3.28 x 10-6 m3
E)   3.28 x 10-23 m3F) B) and C)
G) B) and E)

Question 12

Which of the following experience the strongest covalent bond?

Accepted Answer

A)   F2
B)   I2
C)   Br2
D)   Cl2E) A) and B)
F) A) and C)

Question 13

What is the dominant intermolecular force for propionic acid?

Accepted Answer

A)   hydrogen bonding
B)   dipole interactions
C)   dispersion
D)   ionic
E)   none of theseF) A) and E)
G) C) and D)

Question 14

Predict the relative magnitudes of intermolecular forces and their effects on physical properties of substances.

Accepted Answer

All intermolecular forces are electrosta...

Question 15

Use the following equation for questions 
 
-The value "nb" that is used in the Van der Waals equation accounts for what INCORRECT assumption?

Accepted Answer

A)   that gaseous collisions are not completely elastic
B)   that gas molecules do take up space
C)   that gas molecules interact with each other
D)   that gas molecules do not travel in straight lines
E)   that the velocity of gas molecules changes with temperatureF) A) and B)
G) A) and C)

Question 16

The boiling point of HCl (188 K)  is lower than that for HI (238 K)  because

Accepted Answer

A)   HI is more polar therefore the intermolecular dipole-dipole forces are stronger in HI.
B)   HCl is more polar therefore the intermolecular dipole-dipole forces are stronger in HI.
C)   the molecular mass of HI is greater than that of HCl.
D)   HI is more polarizable, dispersion forces compensate for the lower dipole forces in HI.
E)   HI is capable of hydrogen bonding, HCl is not.F) B) and E)
G) B) and C)

Question 17

Consider the following three molecules:  The dominant intermolecular force acting in each is, respectively ,

Accepted Answer

A)   dipole-dipole; dipole-dipole; hydrogen bonding.
B)   hydrogen bonding; dispersion forces; dipole-dipole.
C)   hydrogen bonding; ion-ion; dipole-dipole.
D)   hydrogen bonding; dipole-dipole; dispersion forces.
E)   dipole-dipole; dipole-dipole; dipole-dipole.F) A) and E)
G) B) and D)

Question 18

Explain enthalpies of phase changes in terms of intermolecular forces and interpret a pressure-temperature phase diagram of a pure substance.

Accepted Answer

A phase diagram shows which phases are t...

Question 19

Some believe that differences between boiling points are truer indicators of relative intermolecular forces than melting points. Why?

Accepted Answer

Because in vapourization, all ...

Question 20

Explain the properties of solids in terms of the dominant intermolecular forces present.

Accepted Answer

Forces in solids may...

Exam 8: Effects of Intermolecular Forces

In which of the following pure substances will hydrogen bonding be an important intermolecular force? 1) dichloromethane, CH2Cl2, 2) CH3CH2OH, 3) methylamine, (CH3NH2) , 4) trimethylamine, N(CH3) 3

Correct AnswerverifiedShow Answer

Where would you expect Ne to appear in the following sequence of boiling points? He < H2 < N2 < F2 < Ar < O2

Correct AnswerverifiedShow Answer

Explain enthalpies of phase changes in terms of intermolecular forces and interpret a pressure-temperature phase diagram of a pure substance.

Correct AnswerverifiedA phase diagram shows which phases are t...View AnswerShow Answer

How much energy is required when 23 grams of ethanol at 30˚C are vapourized from a "flaming" desert? ΔH˚vap = 39.3 kJ/mol, Tvap = 351 K, ΔH˚fus = 7.61 kJ/mol, Tfus = 156 K, Cethanol = 112 J/mol˚C

Correct AnswerverifiedShow Answer

Which of the following experience the strongest covalent bond?

Correct AnswerverifiedShow Answer

Polonium metal crystallizes in a simple cubic structure. If the atomic radius of polonium is 160 pm, what is the volume of a unit cell?

Correct AnswerverifiedShow Answer

Use the phase diagram of oxygen to estimate the temperature at which liquid oxygen will boil under 0.5 atm external pressure and compare that to the normal boiling point.

Correct AnswerverifiedShow Answer

Which of the following experience the strongest intermolecular forces?

Correct AnswerverifiedShow Answer

List the following three compounds in order of increasing boiling point:

Correct AnswerverifiedShow Answer

Explain the properties of solids in terms of the dominant intermolecular forces present.

Correct AnswerverifiedForces in solids may...View AnswerShow Answer

Use the following equation for questions -The value "nb" that is used in the Van der Waals equation accounts for what INCORRECT assumption?

Correct AnswerverifiedShow Answer

What is the dominant intermolecular force for propionic acid?

Correct AnswerverifiedShow Answer

Consider the following three molecules: The dominant intermolecular force acting in each is, respectively ,

Correct AnswerverifiedShow Answer

Predict the relative magnitudes of intermolecular forces and their effects on physical properties of substances.

Correct AnswerverifiedAll intermolecular forces are electrosta...View AnswerShow Answer

Some believe that differences between boiling points are truer indicators of relative intermolecular forces than melting points. Why?

Correct AnswerverifiedBecause in vapourization, all ...View AnswerShow Answer

30 In the simple cubic crystal structure at right, the unit cell is outlined in heavy lines which intersect to form the corners at the center of the spheres. If the corners of the unit cells are at the center of the spheres, how many atoms are in one unit cell?

Correct AnswerverifiedShow Answer

Define supercritical fluid and how to make such a fluid.

Correct AnswerverifiedA supercritical fluid is one t...View AnswerShow Answer

The boiling point of HCl (188 K) is lower than that for HI (238 K) because

Correct AnswerverifiedShow Answer

Which is the most realistic picture for a container of Ar(l) ?

Correct AnswerverifiedShow Answer

Of the following pairs, select the pair that undergoes hydrogen bonding and draw a molecular picture of the hydrogen bond interaction. 1. NaCl and acetone, (CH3)2CO 2. CH3OCH3 and CF3Cl 3. NH3 and CCl4 4. NF3 and CF4 5. CH3NH2 and CH3OCH3

Correct Answerverified#5 undergo...View AnswerShow Answer

In which of the following pure substances will hydrogen bonding be an important intermolecular force? 1) dichloromethane, CH₂Cl₂_, 2) CH₃CH₂OH, 3) methylamine, (CH₃NH₂) , 4) trimethylamine, N(CH₃) ₃

Correct Answer
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Where would you expect Ne to appear in the following sequence of boiling points? He < H₂< N₂< F₂< Ar < O₂

Correct Answer
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Correct Answer
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A phase diagram shows which phases are t...
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How much energy is required when 23 grams of ethanol at 30˚C are vapourized from a "flaming" desert? ΔH˚_vap = 39.3 kJ/mol, T_vap = 351 K, ΔH˚_fus = 7.61 kJ/mol, T_fus = 156 K, C_ethanol = 112 J/mol˚C

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Forces in solids may...
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Correct Answer
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Correct Answer
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Correct Answer
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All intermolecular forces are electrosta...
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Correct Answer
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Because in vapourization, all ...
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Correct Answer
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Correct Answer
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A supercritical fluid is one t...
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Correct Answer
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Correct Answer
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Of the following pairs, select the pair that undergoes hydrogen bonding and draw a molecular picture of the hydrogen bond interaction. 1. NaCl and acetone, (CH₃)₂CO 2. CH₃OCH₃ and CF₃Cl 3. NH₃ and CCl₄ 4. NF₃ and CF₄ 5. CH₃NH₂ and CH₃OCH₃

Correct Answer
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#5 undergo...
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