At low temperatures, the heat capacity of some metals has been found to follow a modified version of the Debye T3 law, varying with temperature according to the relationship Cp.m=aT3+bT With the additional, linear term arising from the electrons. Derive an expression for the molar entropy of such a metal at a low temperature T.

A) S(T)=⅓aT2 B) S(T)=aT2+bT C) S(T)=⅓aT2+bT D) bT A) S(T)=⅓aT2 B) S(T)=aT2+bT C) S(T)=⅓aT2+bT D) bT C

The boiling temperature of cyclohexane, C6H12, is 354 K. Use Trouton's rule to estimate the enthalpy of vaporization of cyclohexane.

A) 6.89 kJ mol-1 B) 18.7 kJ mol-1 C) 85 kJ mol-1 D) 30.1 kJ mol-1 A) 6.89 kJ mol-1 B) 18.7 kJ mol-1 C) 85 kJ mol-1 D) 30.1 kJ mol-1 D

Calculate the standard molar entropy of vaporization of phosphorus trichloride, PCl3, at its boiling temperature, 74 °C, given that the standard molar enthalpy of vaporization of phosphorus trichloride is 30.5 kJ mol-1.

A) +2.43 J K-1 mol-1 B) +109 J K-1 mol-1 C) +412 J K-1 mol-1 D) +78.9 J K-1 mol-1 A) +2.43 J K-1 mol-1 B) +109 J K-1 mol-1 C) +412 J K-1 mol-1 D) +78.9 J K-1 mol-1

A hypothetical system consists of four molecules with a total energy 4F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10Calculate the total number of ways of distributing four quanta of energy F1F1F1S1F1F1F10 amongst the four molecules.

A) 4 B) 70 C) 35 D) 12 A) 4 B) 70 C) 35 D) 12

Exam 3: The Second Law of Thermodynamics

At low temperatures, the heat capacity of some metals has been found to follow a modified version of the Debye T³ law, varying with temperature according to the relationship C_p.m=aT³+bT With the additional, linear term arising from the electrons. Derive an expression for the molar entropy of such a metal at a low temperature T.

Free

(Multiple Choice)

4.9/5

(31)

Question 1

Correct Answer:

Verified

The boiling temperature of cyclohexane, C₆H₁₂, is 354 K. Use Trouton's rule to estimate the enthalpy of vaporization of cyclohexane.

Free

(Multiple Choice)

4.9/5

(33)

Question 2

Correct Answer:

Verified

Calculate the change in the standard molar entropy of sulfur trioxide gas, SO₃, when it is cooled from a temperature of 100 °C to 10 °C at a constant pressure of 1 bar. The standard molar constant-pressure heat capacity of sulfur trioxide is 50.1 J K^-1 mol^-1.

Free

(Multiple Choice)

5.0/5

(33)

Question 3

Correct Answer:

Verified

Calculate the standard molar entropy of vaporization of phosphorus trichloride, PCl₃, at its boiling temperature, 74 °C, given that the standard molar enthalpy of vaporization of phosphorus trichloride is 30.5 kJ mol^-1.

(Multiple Choice)

4.9/5

(39)

Question 4

For hydrogen sulfide, H₂S, the standard enthalpy of formation is -20.2 kJ mol^-1 and the standard entropy of formation is +43.0 J mol^-1 at 298 K. Calculate the standard Gibbs energy of formation at this temperature.

(Multiple Choice)

5.0/5

(31)

Question 5

A hypothetical system consists of four molecules with a total energy 4Calculate the total number of ways of distributing four quanta of energy  amongst the four molecules.

(Multiple Choice)

4.9/5

(32)

Question 6

Calculate the change in the entropy of a large system when 500 J of energy is transferred from the system to the surroundings as heat in an exothermic process at a temperature of 298 K.

(Multiple Choice)

4.8/5

(39)

Question 7

Use the following data to calculate the standard reaction entropy at 298 K for the thermal decomposition of ammonium chloride, NH₄Cl NH₄Cl(s)  NH₃(g) + HCl(g) S_m^o / J mol^-1 NH₄Cl(s) 94.85 NH₃(g) 192.77 HCl(g) 186.90

(Multiple Choice)

4.9/5

(35)

Question 8

Calculate the entropy of vaporization of ethanol, C₂H₅OH, at 298 K from the following data. The constant-pressure molar heat capacities of ethanol as liquid and vapour are 111.46 and 65.44 J K^-1 mol^-1 respectively. The enthalpy of vaporization of ethanol at its boiling temperature, 352 K, is 38.56 kJ mol^-1.

(Multiple Choice)

4.8/5

(44)

Question 9

Calculate the change in the molar entropy of a perfect gas when it is compressed isothermally to 10% of its initial volume.

(Multiple Choice)

4.8/5

(27)

Question 10

Showing 1 - 10 of 10

The boiling temperature of cyclohexane, C₆H₁₂, is 354 K. Use Trouton's rule to estimate the enthalpy of vaporization of cyclohexane.

Calculate the change in the standard molar entropy of sulfur trioxide gas, SO₃, when it is cooled from a temperature of 100 °C to 10 °C at a constant pressure of 1 bar. The standard molar constant-pressure heat capacity of sulfur trioxide is 50.1 J K^-1 mol^-1.

Calculate the standard molar entropy of vaporization of phosphorus trichloride, PCl₃, at its boiling temperature, 74 °C, given that the standard molar enthalpy of vaporization of phosphorus trichloride is 30.5 kJ mol^-1.

For hydrogen sulfide, H₂S, the standard enthalpy of formation is -20.2 kJ mol^-1 and the standard entropy of formation is +43.0 J mol^-1 at 298 K. Calculate the standard Gibbs energy of formation at this temperature.

A hypothetical system consists of four molecules with a total energy 4Calculate the total number of ways of distributing four quanta of energy  amongst the four molecules.

Calculate the change in the entropy of a large system when 500 J of energy is transferred from the system to the surroundings as heat in an exothermic process at a temperature of 298 K.

Use the following data to calculate the standard reaction entropy at 298 K for the thermal decomposition of ammonium chloride, NH₄Cl NH₄Cl(s)  NH₃(g) + HCl(g) S_m^o / J mol^-1 NH₄Cl(s) 94.85 NH₃(g) 192.77 HCl(g) 186.90

Calculate the change in the molar entropy of a perfect gas when it is compressed isothermally to 10% of its initial volume.

The Propertiesof Gases

The First Law of Thermodynamics

Physical Transformations

Chemical Change

Chemical Kinetics

Quantum Theory

Atomic Structure

The Chemical Bond

Molecular Interactions

Molecular Spectroscopy

Statistical Thermodynamics

Filters

Exam 3: The Second Law of Thermodynamics

The boiling temperature of cyclohexane, C6H12, is 354 K. Use Trouton's rule to estimate the enthalpy of vaporization of cyclohexane.

Calculate the change in the standard molar entropy of sulfur trioxide gas, SO3, when it is cooled from a temperature of 100 °C to 10 °C at a constant pressure of 1 bar. The standard molar constant-pressure heat capacity of sulfur trioxide is 50.1 J K-1 mol-1.

Calculate the standard molar entropy of vaporization of phosphorus trichloride, PCl3, at its boiling temperature, 74 °C, given that the standard molar enthalpy of vaporization of phosphorus trichloride is 30.5 kJ mol-1.

For hydrogen sulfide, H2S, the standard enthalpy of formation is -20.2 kJ mol-1 and the standard entropy of formation is +43.0 J mol-1 at 298 K. Calculate the standard Gibbs energy of formation at this temperature.

A hypothetical system consists of four molecules with a total energy 4Calculate the total number of ways of distributing four quanta of energy  amongst the four molecules.

Calculate the change in the entropy of a large system when 500 J of energy is transferred from the system to the surroundings as heat in an exothermic process at a temperature of 298 K.

Use the following data to calculate the standard reaction entropy at 298 K for the thermal decomposition of ammonium chloride, NH4Cl NH4Cl(s)  NH3(g) + HCl(g) Smo / J mol-1 NH4Cl(s) 94.85 NH3(g) 192.77 HCl(g) 186.90

Calculate the change in the molar entropy of a perfect gas when it is compressed isothermally to 10% of its initial volume.

The Propertiesof Gases

The First Law of Thermodynamics

Physical Transformations

Chemical Change

Chemical Kinetics

Quantum Theory

Atomic Structure

The Chemical Bond

Molecular Interactions

Molecular Spectroscopy

Statistical Thermodynamics

Filters

The boiling temperature of cyclohexane, C₆H₁₂, is 354 K. Use Trouton's rule to estimate the enthalpy of vaporization of cyclohexane.

Calculate the change in the standard molar entropy of sulfur trioxide gas, SO₃, when it is cooled from a temperature of 100 °C to 10 °C at a constant pressure of 1 bar. The standard molar constant-pressure heat capacity of sulfur trioxide is 50.1 J K^-1 mol^-1.

Calculate the standard molar entropy of vaporization of phosphorus trichloride, PCl₃, at its boiling temperature, 74 °C, given that the standard molar enthalpy of vaporization of phosphorus trichloride is 30.5 kJ mol^-1.

For hydrogen sulfide, H₂S, the standard enthalpy of formation is -20.2 kJ mol^-1 and the standard entropy of formation is +43.0 J mol^-1 at 298 K. Calculate the standard Gibbs energy of formation at this temperature.

Use the following data to calculate the standard reaction entropy at 298 K for the thermal decomposition of ammonium chloride, NH₄Cl NH₄Cl(s)  NH₃(g) + HCl(g) S_m^o / J mol^-1 NH₄Cl(s) 94.85 NH₃(g) 192.77 HCl(g) 186.90