Question 1

A system absorbs 21.6 kJ of heat while performing 6.9 kJ of work on the surroundings. If the initial internal energy, U, is 61.2 kJ, what is the final value of U?

Accepted Answer

A)   32.7 kJ
B)   46.5 kJ
C)   61.2 kJ
D)   75.9 kJ
E)   89.7 kJF) A) and D)
G) B) and D)

Question 2

A system initially has an internal energy U of 504 J. It undergoes a process during which it releases 111 J of heat energy to the surroundings, and does work of 222 J. What is the final energy of the system, in J?

Accepted Answer

A)   171 J
B)   393 J
C)   504 J
D)   615 J
E)   837 JF) None of the above
G) A) and C)

Question 3

A Snickers® candy bar contains 280 Calories, of which the fat content accounts for 120 Calories. What is the energy of the fat content, in kJ? (1 cal = 4.184 J)

Accepted Answer

A)   5.0 × 10-1 kJ
B)   1.2 kJ
C)   5.0 × 102 kJ
D)   1.2 × 103 kJ
E)   1.6 × 103 kJF) B) and E)
G) None of the above

Question 4

The sign of q when heat is absorbed by the system is ________.

Accepted Answer

The answer of The sign of q when heat is...

Question 5

Suppose a sample of gas undergoes the following change of state.  Which statement(s)  is/are true concerning this change of state?

Accepted Answer

A)   I only
B)   II only
C)   II and III
D)   II and IV
E)   I and IIIF) All of the above
G) A) and E)

Question 6

An exothermic reaction causes the surroundings to

Accepted Answer

A)   warm up.
B)   become acidic.
C)   expand.
D)   decrease its temperature.
E)   release CO2.F) A) and B)
G) D) and E)

Question 7

Ethylene glycol, used as a coolant in automotive engines, has a specific heat capacity of 2.42 J/g°C. Calculate q when 3.65 kg of ethylene glycol is cooled from 132°C to 85°C.

Accepted Answer

A)   -1900 kJ
B)   -420 kJ
C)   -99 kJ
D)   -0.42 kJ
E)   -4.2 × 10-6 kJF) B) and E)
G) A) and D)

Question 8

In an endothermic process, heat is absorbed by the system.

Accepted Answer

A) True 
 B)False

Question 9

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide according to the following balanced chemical equation. What is ΔH°rxn for this reaction? 4NH3(g)  + 5O2(g)  → 4NO(g)  + 6H2O(g)  rxn for this reaction? 4NH3(g)  + 5O2(g)  → 4NO(g)  + 6H2O(g)    A)  -1274.8 kJ/mol B)  -904.4 kJ/mol C)  -240.2 kJ/mol D)  -197.8kJ E)  197.8 kJ/mol" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   -1274.8 kJ/mol
B)   -904.4 kJ/mol
C)   -240.2 kJ/mol
D)   -197.8kJ
E)   197.8 kJ/molF) A) and D)
G) A) and C)

Question 10

The specific heat (capacity)  is

Accepted Answer

A)   the amount of energy needed to increase the temperature of 1 g of a substance by 1°C.
B)   the amount of energy needed to increase the temperature of 1 mol of a substance by 1°C.
C)   the amount of energy required to melt 1 g of substance.
D)   the amount of substance that is heated by 1°C.
E)   the temperature increase, in K, associated with heating 1 g of a substance for 1 minute.F) None of the above
G) A) and B)

Question 11

What is the standard enthalpy change for the decomposition of one mole of SO3? 2SO2 + O2→ 2SO3 ΔH°rxn = -198 kJ/mol

Accepted Answer

A)   198 kJ/mol
B)   -99.0 kJ/mol
C)   99.0 kJ/mol
D)   396 kJ/mol
E)   -396 kJ/molF) A) and D)
G) A) and C)

Question 12

A student used a bomb calorimeter to determine the heat of combustion of an unknown compound. If the student ignored the heat capacity of the bomb calorimeter, the heat capacity of the unknown compound would be ________ the accepted value.

Accepted Answer

A)   greater than (i.e., less negative) 
B)   less than (i.e., more negative) 
C)   equal toD) All of the above
E) None of the above

Question 13

How much heat is required to raise the temperature of 12.0 g of water from 15.4°C to 93.0°C? The specific heat of water is 4.184 J/g·°C.

Accepted Answer

A)   223 J
B)   773 J
C)   503 J
D)   4.67 ×103 J
E)   3.90 ×103 JF) B) and C)
G) A) and E)

Question 14

The work done on the surroundings by the expansion of a gas is w = -PΔV.

Accepted Answer

A) True 
 B)False

Question 15

The bond enthalpy of the Br-Cl bond is equal to ΔH°rxn for the following reaction. BrCl(g)  → Br(g)  + Cl(g) 
Using the following data, what is the bond enthalpy of the Br-Cl bond? rxn for the following reaction. BrCl(g)  → Br(g)  + Cl(g)  Using the following data, what is the bond enthalpy of the Br-Cl bond?   A)  219.0 kJ/mol B)  203.5 kJ/mol C)  14.6 kJ/mol D)  438.0 kJ/mol E)  407.0 kJ/mol" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   219.0 kJ/mol
B)   203.5 kJ/mol
C)   14.6 kJ/mol
D)   438.0 kJ/mol
E)   407.0 kJ/molF) A) and E)
G) B) and D)

Question 16

Which type of system may transfer energy, but not mass, to the surroundings?

Accepted Answer

A)   mass transfer system
B)   isolated system
C)   closed system
D)   nonenergy system
E)   open systemF) B) and C)
G) None of the above

Question 17

The heat of solution of ammonium chloride is 15.2 kJ/mol. If a 6.134-g sample of NH4Cl is added to 65.0 mL of water in a calorimeter at 24.5°C, what is the final temperature of the solution? The specific heat of water is 4.18 J/g·°C and the heat capacity of the calorimeter is 365 J/°C.

Accepted Answer

A)   27.1°C
B)   18.6°C
C)   19.7°C
D)   21.8°C
E)   30.4°CF) D) and E)
G) None of the above

Question 18

Styrene, C8H8, is one of the substances used in the production of synthetic rubber. When styrene burns in oxygen to form carbon dioxide and liquid water under standard-state conditions at 25°C, 42.15 kJ are released per gram of styrene. Find the standard enthalpy of formation of styrene at 25°C. ΔH°f(CO2(g) )  = -393.5 kJ/mol, ΔH°f(H2O(l) )  = -285.8 kJ/mol

Accepted Answer

A)   -4390 kJ/mol
B)   -1044 kJ/mol
C)   -8681 kJ/mol
D)   +99 kJ/mol
E)   +637 kJ/molF) B) and E)
G) D) and E)

Question 19

A system that does no work but which receives heat from the surroundings has

Accepted Answer

A)   q  0.
B)   q > 0, ΔU 
C)   q = ΔU.
D)   q = -ΔU.
E)   w = ΔU.F) C) and D)
G) A) and B)

Question 20

A system that does no work but which transfers heat to the surroundings has

Accepted Answer

A)   q  0.
B)   q 
C)   q > 0, ΔU > 0.
D)   q > 0, ΔU 
E)   q < 0, ΔU = 0.F) B) and C)
G) D) and E)

Exam 5: Thermochemistry

A system initially has an internal energy U of 504 J. It undergoes a process during which it releases 111 J of heat energy to the surroundings, and does work of 222 J. What is the final energy of the system, in J?

Correct Answer
verified

The work done on the surroundings by the expansion of a gas is w = -PΔV.

Correct Answer
verified

What is the standard enthalpy change for the decomposition of one mole of SO₃? 2SO₂ + O₂→ 2SO₃ΔH°_rxn = -198 kJ/mol

Correct Answer
verified

A system absorbs 21.6 kJ of heat while performing 6.9 kJ of work on the surroundings. If the initial internal energy, U, is 61.2 kJ, what is the final value of U?

Correct Answer
verified

The specific heat (capacity) is

Correct Answer
verified

A system that does no work but which receives heat from the surroundings has

Correct Answer
verified

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide according to the following balanced chemical equation. What is ΔH°_rxn for this reaction? 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)

Correct Answer
verified

A Snickers® candy bar contains 280 Calories, of which the fat content accounts for 120 Calories. What is the energy of the fat content, in kJ? (1 cal = 4.184 J)

Correct Answer
verified

The sign of q when heat is absorbed by the system is ________.

Correct Answer
verified

A student used a bomb calorimeter to determine the heat of combustion of an unknown compound. If the student ignored the heat capacity of the bomb calorimeter, the heat capacity of the unknown compound would be ________ the accepted value.

Correct Answer
verified

How much heat is required to raise the temperature of 12.0 g of water from 15.4°C to 93.0°C? The specific heat of water is 4.184 J/g·°C.

Correct Answer
verified

Ethylene glycol, used as a coolant in automotive engines, has a specific heat capacity of 2.42 J/g°C. Calculate q when 3.65 kg of ethylene glycol is cooled from 132°C to 85°C.

Correct Answer
verified

Which type of system may transfer energy, but not mass, to the surroundings?

Correct Answer
verified

A system that does no work but which transfers heat to the surroundings has

Correct Answer
verified

Correct Answer
verified

In an endothermic process, heat is absorbed by the system.

Correct Answer
verified

Suppose a sample of gas undergoes the following change of state. Which statement(s) is/are true concerning this change of state?

Correct Answer
verified

The heat of solution of ammonium chloride is 15.2 kJ/mol. If a 6.134-g sample of NH₄Cl is added to 65.0 mL of water in a calorimeter at 24.5°C, what is the final temperature of the solution? The specific heat of water is 4.18 J/g·°C and the heat capacity of the calorimeter is 365 J/°C.

Correct Answer
verified

An exothermic reaction causes the surroundings to

Correct Answer
verified

The bond enthalpy of the Br-Cl bond is equal to ΔH°_rxn for the following reaction. BrCl(g) → Br(g) + Cl(g) Using the following data, what is the bond enthalpy of the Br-Cl bond?

Correct Answer
verified

Exam 5: Thermochemistry

A system initially has an internal energy U of 504 J. It undergoes a process during which it releases 111 J of heat energy to the surroundings, and does work of 222 J. What is the final energy of the system, in J?

Correct AnswerverifiedShow Answer

The work done on the surroundings by the expansion of a gas is w = -PΔV.

Correct AnswerverifiedShow Answer

What is the standard enthalpy change for the decomposition of one mole of SO3? 2SO2 + O2→ 2SO3 ΔH°rxn = -198 kJ/mol

Correct AnswerverifiedShow Answer

A system absorbs 21.6 kJ of heat while performing 6.9 kJ of work on the surroundings. If the initial internal energy, U, is 61.2 kJ, what is the final value of U?

Correct AnswerverifiedShow Answer

The specific heat (capacity) is

Correct AnswerverifiedShow Answer

A system that does no work but which receives heat from the surroundings has

Correct AnswerverifiedShow Answer

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide according to the following balanced chemical equation. What is ΔH°rxn for this reaction? 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g)

Correct AnswerverifiedShow Answer

A Snickers® candy bar contains 280 Calories, of which the fat content accounts for 120 Calories. What is the energy of the fat content, in kJ? (1 cal = 4.184 J)

Correct AnswerverifiedShow Answer

The sign of q when heat is absorbed by the system is ________.

Correct AnswerverifiedShow Answer

A student used a bomb calorimeter to determine the heat of combustion of an unknown compound. If the student ignored the heat capacity of the bomb calorimeter, the heat capacity of the unknown compound would be ________ the accepted value.

Correct AnswerverifiedShow Answer

How much heat is required to raise the temperature of 12.0 g of water from 15.4°C to 93.0°C? The specific heat of water is 4.184 J/g·°C.

Correct AnswerverifiedShow Answer

Ethylene glycol, used as a coolant in automotive engines, has a specific heat capacity of 2.42 J/g°C. Calculate q when 3.65 kg of ethylene glycol is cooled from 132°C to 85°C.

Correct AnswerverifiedShow Answer

Which type of system may transfer energy, but not mass, to the surroundings?

Correct AnswerverifiedShow Answer

A system that does no work but which transfers heat to the surroundings has

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

In an endothermic process, heat is absorbed by the system.

Correct AnswerverifiedShow Answer

Suppose a sample of gas undergoes the following change of state. Which statement(s) is/are true concerning this change of state?

Correct AnswerverifiedShow Answer

The heat of solution of ammonium chloride is 15.2 kJ/mol. If a 6.134-g sample of NH4Cl is added to 65.0 mL of water in a calorimeter at 24.5°C, what is the final temperature of the solution? The specific heat of water is 4.18 J/g·°C and the heat capacity of the calorimeter is 365 J/°C.

Correct AnswerverifiedShow Answer

An exothermic reaction causes the surroundings to

Correct AnswerverifiedShow Answer

The bond enthalpy of the Br-Cl bond is equal to ΔH°rxn for the following reaction. BrCl(g) → Br(g) + Cl(g) Using the following data, what is the bond enthalpy of the Br-Cl bond?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

What is the standard enthalpy change for the decomposition of one mole of SO₃? 2SO₂ + O₂→ 2SO₃ΔH°_rxn = -198 kJ/mol

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide according to the following balanced chemical equation. What is ΔH°_rxn for this reaction? 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The heat of solution of ammonium chloride is 15.2 kJ/mol. If a 6.134-g sample of NH₄Cl is added to 65.0 mL of water in a calorimeter at 24.5°C, what is the final temperature of the solution? The specific heat of water is 4.18 J/g·°C and the heat capacity of the calorimeter is 365 J/°C.

Correct Answer
verified

Correct Answer
verified

The bond enthalpy of the Br-Cl bond is equal to ΔH°_rxn for the following reaction. BrCl(g) → Br(g) + Cl(g) Using the following data, what is the bond enthalpy of the Br-Cl bond?

Correct Answer
verified