Question 1

Why is the ΔvapH higher than ΔfusH for a given compound?

Accepted Answer

Vaporizing a substance requires the complete "breaking" of all intermolecular attractions, whereas the melting of a substance only requires the breaking of a portion of the intermolecular attractions.

Question 2

Determine the vapour pressure (in mbar) of a substance at 36 °C whose normal boiling point is 84 °C and has a ΔvapH of 22.1 kJ mol-1.

Accepted Answer

A)  319 mbar 
B)  31.8 mbar 
C)  41.8 mbar 
D)  147 mbar 
E)  98 mbar 
A)  319 mbar 
B)  31.8 mbar 
C)  41.8 mbar 
D)  147 mbar 
E)  98 mbar A

Question 3

Identify the type of solid for argon.

Accepted Answer

A)  metallic atomic solid 
B)  ionic solid 
C)  nonbonding atomic solid 
D)  molecular solid 
E)  networking atomic solid 
A)  metallic atomic solid 
B)  ionic solid 
C)  nonbonding atomic solid 
D)  molecular solid 
E)  networking atomic solid C

Question 4

The enthalpy change for converting 1.00 mol of ice at -60.0°C to water at 80.0°C is   The specific heats of ice, water, and steam are     and   respectively. For   O,   = 6.01 kJ mol-1, and   .

Accepted Answer

A)  9.77 
B)  14.29 
C)  8282 
D)  13.17 
E)  48.95 
A)  9.77 
B)  14.29 
C)  8282 
D)  13.17 
E)  48.95

Question 5

Which of the following forms an ionic solid?

Accepted Answer

A)  Cr 
B)  C4H9NH2 
C)  Cs NO3 
D)  N O4 
A)  Cr 
B)  C4H9NH2 
C)  Cs NO3 
D)  N O4

Question 6

Describe the difference between the conduction band and the valence band.

Accepted Answer

The valence band is the group of highest

Question 7

Which of the following substances would you predict to have the highest ΔvapH?

Accepted Answer

A)  Xe 
B)  C6H6 
C)  SiF4 
D)  Br2 
E)  N2 
A)  Xe 
B)  C6H6 
C)  SiF4 
D)  Br2 
E)  N2

Question 8

Choose the substance with the lowest boiling point.

Accepted Answer

A)  H2S 
B)  NBr3 
C)  F2 
D)  CF2H2 
E)  H2O2 
A)  H2S 
B)  NBr3 
C)  F2 
D)  CF2H2 
E)  H2O2

Question 9

Choose the compound that exhibits hydrogen bonding as its strongest intermolecular force.

Accepted Answer

A)  SCl2 
B)  C2H6 
C)  CH3OH 
D)  CH2F2 
E)  None of the above compounds exhibit hydrogen bonding. 
A)  SCl2 
B)  C2H6 
C)  CH3OH 
D)  CH2F2 
E)  None of the above compounds exhibit hydrogen bonding.

Question 10

Choose the substance with the highest boiling point.

Accepted Answer

A)  CH4 
B)  CH3CH3 
C)  CH3CH2Cl 
D)  CH3CH2CH2OH 
E)  H2 
A)  CH4 
B)  CH3CH3 
C)  CH3CH2Cl 
D)  CH3CH2CH2OH 
E)  H2

Question 11

The enthalpy change for converting 10.0 g of ice at -25.0 °C to water at 80.0 °C is ________ kJ. The specific heats of ice, water, and steam are     and   respectively. For   O,   = 6.01 kJ mol-1, and   .

Accepted Answer

A)  7.21 
B)  6.16 
C)  3870 
D)  63.97 
E)  26.46 
A)  7.21 
B)  6.16 
C)  3870 
D)  63.97 
E)  26.46

Question 12

Identify the term used to describe the ability of a liquid to flow against gravity up a narrow tube.

Accepted Answer

A)  capillary action 
B)  viscosity 
C)  surface tension 
D)  density 
A)  capillary action 
B)  viscosity 
C)  surface tension 
D)  density

Question 13

Vanadium crystallizes in a body-centred cubic structure and has an atomic radius of 131 pm. Determine the density of vanadium if the edge length of a bcc structure is 4r/   .

Accepted Answer

A)  3.06 g cm-3 
B)  12.2 g cm-3 
C)  6.11 g cm-3 
D)  2.77 g cm-3 
E)  8.46 g cm-3 
A)  3.06 g cm-3 
B)  12.2 g cm-3 
C)  6.11 g cm-3 
D)  2.77 g cm-3 
E)  8.46 g cm-3

Question 14

What type of intermolecular force causes the dissolution of CH3CH2OH in water?

Accepted Answer

A)  hydrogen bonding 
B)  dipole-dipole forces 
C)  ion-dipole forces 
D)  dispersion forces 
E)  none of the above 
A)  hydrogen bonding 
B)  dipole-dipole forces 
C)  ion-dipole forces 
D)  dispersion forces 
E)  none of the above

Question 15

Which type of bonding does Sr form upon solidification?

Accepted Answer

A)  covalent network 
B)  ionic 
C)  metallic 
D)  molecular 
A)  covalent network 
B)  ionic 
C)  metallic 
D)  molecular

Question 16

Give the coordination number for a body-centred cubic cell.

Accepted Answer

A)  4 
B)  6 
C)  8 
D)  10 
E)  12 
A)  4 
B)  6 
C)  8 
D)  10 
E)  12

Question 17

Based on the figure above, the boiling point of diethyl ether under an external pressure of 1.32   is ________ °C.

Accepted Answer

A)  10 
B)  20 
C)  30 
D)  40 
E)  0 
A)  10 
B)  20 
C)  30 
D)  40 
E)  0

Question 18

Choose the pair of substances that are most likely to form a homogeneous solution.

Accepted Answer

A)  CCl4 and SCl2 
B)  NF3 and SO2 
C)  CO and C6H6 
D)  NH2CH3 and CH4 
E)  None of the pairs above will form a homogeneous solution. 
A)  CCl4 and SCl2 
B)  NF3 and SO2 
C)  CO and C6H6 
D)  NH2CH3 and CH4 
E)  None of the pairs above will form a homogeneous solution.

Question 19

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l) at 35.0 °C to gaseous CCl4 at 76.8 °C (the normal boiling point for CCl4). The specific heat of CCl4(l) is   its heat of fusion is   and its heat of vaporization is

Accepted Answer

A)  0.896 kJ 
B)  1.43 kJ 
C)  5.74 kJ 
D)  6.28 kJ 
A)  0.896 kJ 
B)  1.43 kJ 
C)  5.74 kJ 
D)  6.28 kJ

Question 20

How much energy is required to vaporize 98.6 g of ethanol (C2H5OH) at its boiling point if its ΔvapH is 40.5 kJ mol-1?

Accepted Answer

A)  86.7 kJ 
B)  11.5 kJ 
C)  18.9 kJ 
D)  52.8 kJ 
E)  39.9 kJ 
A)  86.7 kJ 
B)  11.5 kJ 
C)  18.9 kJ 
D)  52.8 kJ 
E)  39.9 kJ

Exam 11: Liquids, Solids, and Intermolecular Forces

Why is the ΔvapH higher than ΔfusH for a given compound?

Determine the vapour pressure (in mbar) of a substance at 36 °C whose normal boiling point is 84 °C and has a ΔvapH of 22.1 kJ mol-1.

Identify the type of solid for argon.

The enthalpy change for converting 1.00 mol of ice at -60.0°C to water at 80.0°C is The specific heats of ice, water, and steam are and respectively. For O, = 6.01 kJ mol-1, and .

Which of the following forms an ionic solid?

Describe the difference between the conduction band and the valence band.

Which of the following substances would you predict to have the highest ΔvapH?

Choose the substance with the lowest boiling point.

Choose the compound that exhibits hydrogen bonding as its strongest intermolecular force.

Choose the substance with the highest boiling point.

The enthalpy change for converting 10.0 g of ice at -25.0 °C to water at 80.0 °C is ________ kJ. The specific heats of ice, water, and steam are and respectively. For O, = 6.01 kJ mol-1, and .

Identify the term used to describe the ability of a liquid to flow against gravity up a narrow tube.

Vanadium crystallizes in a body-centred cubic structure and has an atomic radius of 131 pm. Determine the density of vanadium if the edge length of a bcc structure is 4r/ .

What type of intermolecular force causes the dissolution of CH3CH2OH in water?

Which type of bonding does Sr form upon solidification?

Give the coordination number for a body-centred cubic cell.

Based on the figure above, the boiling point of diethyl ether under an external pressure of 1.32 is ________ °C.

Choose the pair of substances that are most likely to form a homogeneous solution.

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l) at 35.0 °C to gaseous CCl4 at 76.8 °C (the normal boiling point for CCl4). The specific heat of CCl4(l) is its heat of fusion is and its heat of vaporization is

How much energy is required to vaporize 98.6 g of ethanol (C2H5OH) at its boiling point if its ΔvapH is 40.5 kJ mol-1?

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Chemical Reactions and Stoichiometry

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

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Chemistry of the Nonmetals

Metals and Metallurgy

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Filters

Why is the Δ_vapH higher than Δ_fusHfor a given compound?

Determine the vapour pressure (in mbar) of a substance at 36 °C whose normal boiling point is 84 °C and has a Δ_vapHof 22.1 kJ mol^-1.

The enthalpy change for converting 1.00 mol of ice at -60.0°C to water at 80.0°C is The specific heats of ice, water, and steam are and respectively. For O, = 6.01 kJ mol^-1, and .

Which of the following substances would you predict to have the highest Δ_vapH?

The enthalpy change for converting 10.0 g of ice at -25.0 °C to water at 80.0 °C is ________ kJ. The specific heats of ice, water, and steam are and respectively. For O, = 6.01 kJ mol^-1, and .

What type of intermolecular force causes the dissolution of CH₃CH₂OH in water?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl₄(l) at 35.0 °C to gaseous CCl₄ at 76.8 °C (the normal boiling point for CCl₄). The specific heat of CCl₄(l) is its heat of fusion is and its heat of vaporization is

How much energy is required to vaporize 98.6 g of ethanol (C₂H₅OH) at its boiling point if its Δ_vapH is 40.5 kJ mol^-1?