Question 1

What is the strongest type of intermolecular force present in Cl2?

Accepted Answer

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

Question 2

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l)from 35.0°C to gaseous CCl4 at 76.8°C (the normal boiling point for CCl4).The specific heat of CCl4(l)is 0.857 J/(g ∙ °C),its heat of fusion is 3.27 kJ/mol,and its heat of vaporization is 29.82` kJ/mol.

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 3

Place the following substances in order of decreasing vapor pressure at a given temperature. BeF2 CH3OH OF2

Accepted Answer

A)  CH3OH > OF2 > BeF2 
B)  BeF2 > OF2 > CH3OH 
C)  OF2 > CH3OH > BeF2 
D)  OF2 > BeF2 > CH3OH 
E)  BeF2 > CH3OH > OF2 
A)  CH3OH > OF2 > BeF2 
B)  BeF2 > OF2 > CH3OH 
C)  OF2 > CH3OH > BeF2 
D)  OF2 > BeF2 > CH3OH 
E)  BeF2 > CH3OH > OF2

Question 4

Define triple point.

Accepted Answer

A)  The temperature, pressure, and density for a gas. 
B)  The temperature at which the boiling point equals the melting point. 
C)  The temperature and pressure where liquid, solid, and gas are equally stable and are in equilibrium. 
D)  The temperature that is unique for a substance. 
E)  The temperature at which the solid and liquid co-exist. 
A)  The temperature, pressure, and density for a gas. 
B)  The temperature at which the boiling point equals the melting point. 
C)  The temperature and pressure where liquid, solid, and gas are equally stable and are in equilibrium. 
D)  The temperature that is unique for a substance. 
E)  The temperature at which the solid and liquid co-exist.

Question 5

What is the heat of vaporization of a compound that has a vapor pressure of 120 mm Hg at 12.3°C and a vapor pressure of 250 mm Hg at 43.6 °C?

Accepted Answer

A)  12.28 kJ/mol 
B)  25.2 kJ/mol 
C)  11.32 kJ/mol 
D)  43.6 kJ/mol 
E)  17.62kJ/mol 
A)  12.28 kJ/mol 
B)  25.2 kJ/mol 
C)  11.32 kJ/mol 
D)  43.6 kJ/mol 
E)  17.62kJ/mol

Question 6

How much energy must be removed from a 125 g sample of benzene (molar mass= 78.11 g/mol)at 425.0 K to liquify the sample and lower the temperature to 335.0 K? The following physical data may be useful.
ΔHvap = 33.9 kJ/mol
ΔHfus = 9.8 kJ/mol
Cliq = 1.73 J/g°C
Cgas = 1.06 J/g°C
Csol = 1.51 J/g°C
Tmelting = 279.0 K
Tboiling = 353.0 K

Accepted Answer

A)  38.9 kJ 
B)  95.4 kJ 
C)  67.7 kJ 
D)  54.3 kJ 
E)  74.4 kJ 
A)  38.9 kJ 
B)  95.4 kJ 
C)  67.7 kJ 
D)  54.3 kJ 
E)  74.4 kJ

Question 7

Determine ΔHvap for a compound that has a measured vapor pressure of 24.3 torr at 273 K and 135 torr at 325 K.

Accepted Answer

A)  41 kJ/mol 
B)  79 kJ/mol 
C)  24 kJ/mol 
D)  13 kJ/mol 
E)  34 kJ/mol 
A)  41 kJ/mol 
B)  79 kJ/mol 
C)  24 kJ/mol 
D)  13 kJ/mol 
E)  34 kJ/mol

Question 8

Ethanol (C2H5OH)melts at -114°C.The enthalpy of fusion is 5.02 kJ/mol.The specific heats of solid and liquid ethanol are 0.97 J/gK and 2.3 J/gK,respectively.How much heat (kJ)is needed to convert 25.0 g of solid ethanol at -135°C to liquid ethanol at -50°C?

Accepted Answer

A)  207.3 kJ 
B)  -12.7 kJ 
C)  6.91 kJ 
D)  4192 kJ 
E)  9.21 kJ 
A)  207.3 kJ 
B)  -12.7 kJ 
C)  6.91 kJ 
D)  4192 kJ 
E)  9.21 kJ

Question 9

Why is the ΔHvap higher than ΔHfus for a given compound?

Accepted Answer

Vaporizing a substance require

Question 10

What happens when the vapor pressure of a liquid is equal to the external pressure?

Accepted Answer

A)  An equilibrium exists between the liquid and the solid state. 
B)  The liquid freezes. 
C)  The intermolecular forces become stronger in the liquid. 
D)  The liquid boils. 
E)  Dispersion forces become weaker in the liquid. 
A)  An equilibrium exists between the liquid and the solid state. 
B)  The liquid freezes. 
C)  The intermolecular forces become stronger in the liquid. 
D)  The liquid boils. 
E)  Dispersion forces become weaker in the liquid.

Question 11

Which one of the following has a definite shape and volume?

Accepted Answer

A)  gas 
B)  liquid 
C)  solid 
D)  none of the above 
E)  all of the above 
A)  gas 
B)  liquid 
C)  solid 
D)  none of the above 
E)  all of the above

Question 12

Calculate the energy that is required to heat 125 g ice at -10.0°C to a temperature of 130.0°C.The heat of fusion = 333 J/g,the heat of vaporization = 2256 J/g,and the specific heat capacities of ice = 2.06 J /g∙K,liquid water = 4.184 J /g∙K,and steam = 2.01 J /g∙K.

Accepted Answer

A)  4.75 × 106 J 
B)  3.87 × 105 J 
C)  1.31 × 105 J 
D)  7.32 × 104 J 
E)  2.88 × 104 J 
A)  4.75 × 106 J 
B)  3.87 × 105 J 
C)  1.31 × 105 J 
D)  7.32 × 104 J 
E)  2.88 × 104 J

What is the strongest type of intermolecular force present in Cl₂?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl₄(l)from 35.0°C to gaseous CCl₄ at 76.8°C (the normal boiling point for CCl₄).The specific heat of CCl₄(l)is 0.857 J/(g ∙ °C),its heat of fusion is 3.27 kJ/mol,and its heat of vaporization is 29.82` kJ/mol.

Place the following substances in order of decreasing vapor pressure at a given temperature. BeF₂ CH₃OH OF₂

Define triple point.

What is the heat of vaporization of a compound that has a vapor pressure of 120 mm Hg at 12.3°C and a vapor pressure of 250 mm Hg at 43.6 °C?

Determine ΔH_vap for a compound that has a measured vapor pressure of 24.3 torr at 273 K and 135 torr at 325 K.

Ethanol (C₂H₅OH)melts at -114°C.The enthalpy of fusion is 5.02 kJ/mol.The specific heats of solid and liquid ethanol are 0.97 J/gK and 2.3 J/gK,respectively.How much heat (kJ)is needed to convert 25.0 g of solid ethanol at -135°C to liquid ethanol at -50°C?

Why is the ΔH_vap higher than ΔH_fusfor a given compound?

What happens when the vapor pressure of a liquid is equal to the external pressure?

Which one of the following has a definite shape and volume?

Calculate the energy that is required to heat 125 g ice at -10.0°C to a temperature of 130.0°C.The heat of fusion = 333 J/g,the heat of vaporization = 2256 J/g,and the specific heat capacities of ice = 2.06 J /g∙K,liquid water = 4.184 J /g∙K,and steam = 2.01 J /g∙K.

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Crystalline Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

Exam 12: Liquids, Solids, and Intermolecular Forces

What is the strongest type of intermolecular force present in Cl2?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l)from 35.0°C to gaseous CCl4 at 76.8°C (the normal boiling point for CCl4).The specific heat of CCl4(l)is 0.857 J/(g ∙ °C),its heat of fusion is 3.27 kJ/mol,and its heat of vaporization is 29.82` kJ/mol.

Place the following substances in order of decreasing vapor pressure at a given temperature. BeF2 CH3OH OF2

Define triple point.

What is the heat of vaporization of a compound that has a vapor pressure of 120 mm Hg at 12.3°C and a vapor pressure of 250 mm Hg at 43.6 °C?

Determine ΔHvap for a compound that has a measured vapor pressure of 24.3 torr at 273 K and 135 torr at 325 K.

Ethanol (C2H5OH)melts at -114°C.The enthalpy of fusion is 5.02 kJ/mol.The specific heats of solid and liquid ethanol are 0.97 J/gK and 2.3 J/gK,respectively.How much heat (kJ)is needed to convert 25.0 g of solid ethanol at -135°C to liquid ethanol at -50°C?

Why is the ΔHvap higher than ΔHfus for a given compound?

What happens when the vapor pressure of a liquid is equal to the external pressure?

Which one of the following has a definite shape and volume?

Calculate the energy that is required to heat 125 g ice at -10.0°C to a temperature of 130.0°C.The heat of fusion = 333 J/g,the heat of vaporization = 2256 J/g,and the specific heat capacities of ice = 2.06 J /g∙K,liquid water = 4.184 J /g∙K,and steam = 2.01 J /g∙K.

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Crystalline Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

What is the strongest type of intermolecular force present in Cl₂?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl₄(l)from 35.0°C to gaseous CCl₄ at 76.8°C (the normal boiling point for CCl₄).The specific heat of CCl₄(l)is 0.857 J/(g ∙ °C),its heat of fusion is 3.27 kJ/mol,and its heat of vaporization is 29.82` kJ/mol.

Place the following substances in order of decreasing vapor pressure at a given temperature. BeF₂ CH₃OH OF₂

Determine ΔH_vap for a compound that has a measured vapor pressure of 24.3 torr at 273 K and 135 torr at 325 K.

Ethanol (C₂H₅OH)melts at -114°C.The enthalpy of fusion is 5.02 kJ/mol.The specific heats of solid and liquid ethanol are 0.97 J/gK and 2.3 J/gK,respectively.How much heat (kJ)is needed to convert 25.0 g of solid ethanol at -135°C to liquid ethanol at -50°C?

Why is the ΔH_vap higher than ΔH_fusfor a given compound?