Question 1

Which one of the following is not a correct formation reaction? (products are correct)

Accepted Answer

A)   H2(g)  + O(g)   H2O(l) 
B)   2(g)  + O(g)   H2O(l)  
B)     H2(g)  +   Cl2(g)   HCl(g)  
C)   6C(graphite)  + 3H2(g)   C6H6(l)  
D)   C(graphite)   C(diamond)  
E)   6C(graphite)  + 6H2(g)  + 3O2(g)   C6H12O6(s) " class="answers-bank-image d-inline" rel="preload" > H2(g)  + 2(g)  + O(g)   H2O(l)  
B)     H2(g)  +   Cl2(g)   HCl(g)  
C)   6C(graphite)  + 3H2(g)   C6H6(l)  
D)   C(graphite)   C(diamond)  
E)   6C(graphite)  + 6H2(g)  + 3O2(g)   C6H12O6(s) " class="answers-bank-image d-inline" rel="preload" > Cl2(g)   HCl(g) 
C)   6C(graphite)  + 3H2(g)   C6H6(l) 
D)   C(graphite)   C(diamond) 
E)   6C(graphite)  + 6H2(g)  + 3O2(g)   C6H12O6(s) F) A) and E)
G) A) and B)

Question 2

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide. 4NH3(g)  + 5O2(g)   4NO(g)  + 6H2O(g) 
Calculate H°rxn for this reaction.
H°f [NH3(g) ] = -45.9 kJ/mol; H°f [NO(g) ] = 90.3 kJ/mol; H°f [H2O(g) ] = -241.8 kJ/mol

Accepted Answer

A)   -906.0 kJ
B)   -197.4 kJ
C)   -105.6 kJ
D)   197.4 kJ
E)   906.0 kJF) A) and D)
G) A) and B)

Question 3

Natural gas, or methane, is an important fuel. Combustion of one mole of methane releases 802.3 kilojoules of energy. How much energy does that represent in kilocalories?

Accepted Answer

A)   1.92 × 10-1 kcal
B)   1.92 × 102 kcal
C)   3.36 × 103 kcal
D)   1.92 × 105 kcal
E)   3.36 × 106 kcalF) A) and D)
G) C) and D)

Question 4

For all processes, both q and F1F1F1S1F1F1F10E will have the same sign.

Accepted Answer

A) True 
 B)False

Question 5

Calculate the H°rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide. H°f [CaCO3(s) ] = -1206.9 kJ/mol; H°f [CaO(s) ] = -635.1 kJ/mol; H°f [CO2(g) ] = -393.5 kJ/mol
CaCO3(s)   CaO(s)  + CO2(g)

Accepted Answer

A)   -2235.5 kJ
B)   -1448.5 kJ
C)   -178.3 kJ
D)   178.3 kJ
E)   2235.5 kJF) C) and E)
G) C) and D)

Question 6

a. State Hess's Law.
b. Use the F1F1F1S1F1F1F10H° data given below to calculate F1F1F1S1F1F1F10H° for the reaction:

Accepted Answer

a. The enthalpy change for an ...

Question 7

The standard state of a substance in aqueous solution is a 1 M solution.

Accepted Answer

A) True 
 B)False

Question 8

Calcium hydroxide, which reacts with carbon dioxide to form calcium carbonate, was used by the ancient Romans as mortar in stone structures. The reaction for this process is Ca(OH) 2(s)  + CO2(g)   CaCO3(s)  + H2O(g)  H = -69.1 kJ
What is the enthalpy change if 3.8 mol of calcium carbonate is formed?

Accepted Answer

A)   -18 kJ
B)   -69 kJ
C)   -73 kJ
D)   -260 kJ
E)   none of the aboveF) A) and E)
G) A) and B)

Question 9

The reaction
2NaOH(aq) + H2SO4(aq) F1F1F1S1F1F1F10 Na2SO4(aq) + 2H2O(l)
was studied in a coffee cup calorimeter. 100. mL portions of 1.00 M aqueous NaOH and H2SO4, each at 24.0°C, were mixed. The maximum temperature achieved was 30.6°C. Neglect the heat capacity of the cup and the thermometer, and assume that the solution of products has a density of exactly 1 g/mL and a specific heat capacity of 4.18 J/(g·K).
a. Calculate the heat of reaction, q, in J.
b. Calculate F1F1F1S1F1F1F10H, the heat (enthalpy) of reaction, in kJ/mol of Na2SO4 produced.

Accepted Answer

a. 5.5 × 1...

Question 10

Benzene is a starting material in the synthesis of nylon fibers and polystyrene (styrofoam) . Its specific heat capacity is 1.74 J/(g·K) . If 16.7 kJ of energy is absorbed by a 225-g sample of benzene at 20.0°C, what is its final temperature?

Accepted Answer

A)   -22.7°C
B)   36.7°C
C)   42.7°C
D)   62.7°C
E)   none of the aboveF) A) and D)
G) C) and D)

Question 11

a. Write a balanced equation for the combustion of benzene, C6H6(l) in oxygen.
b. The standard heat of combustion of benzene is -3271 kJ/mol. Calculate its standard heat of formation, F1F1F1S1F1F1F10H°f , given the data:
F1F1F1S1F1F1F10H°f [CO2(g)] = -394 kJ; F1F1F1S1F1F1F10H°f [H2O(l)] = -286 kJ

Accepted Answer

a. C₆H₆(l) + 7.5O₂(g) F1...

Question 12

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

Accepted Answer

A)   32.7 kJ
B)   46.5 kJ
C)   75.9 kJ
D)   82.8 kJ
E)   89.7 kJF) A) and B)
G) B) and C)

Question 13

Which of the following is not a state function?

Accepted Answer

A)   internal energy
B)   volume
C)   work
D)   pressure
E)   enthalpyF) A) and B)
G) A) and C)

Question 14

What is the final temperature when 20.0 g of water at 25°C is mixed with 30.0 g of water at 80°C?

Accepted Answer

A)   35°C
B)   42°C
C)   53°C
D)   58°C
E)   70°CF) C) and D)
G) B) and C)

Question 15

A 275-g sample of nickel at 100.0°C is placed in 100.0 mL of water at 22.0°C. What is the final temperature of the water? Assume that no heat is lost to or gained from the surroundings. Specific heat capacity of nickel = 0.444 J/(g·K)

Accepted Answer

A)   39.6°C
B)   40.8°C
C)   61.0°C
D)   79.2°C
E)   82.4°CF) A) and C)
G) A) and B)

Question 16

Use Hess's Law to calculate the enthalpy change for the reaction 
WO3(s)  + 3H2(g)   W(s)  + 3H2O(g) 
From the following data:
2W(s)  + 3O2(g)   2WO3(s)  H = -1685.4 kJ
2H2(g)  + O2(g)   2H2O(g)  H = -477.84 kJ

Accepted Answer

A)   125.9 kJ
B)   252.9 kJ
C)   364.9 kJ
D)   1207.6 kJ
E)   none of the aboveF) A) and B)
G) A) and C)

Question 17

The standard heat (enthalpy) of formation of graphite is zero.

Accepted Answer

A) True 
 B)False

Question 18

Your favorite candy bar, Gummy Beakers, contains 1.2 × 106 J of energy while your favorite soft drink, Bolt, contains 6.7 × 105 J. If you eat two packs of Gummy Beakers a day and drink 3 cans of Bolt, what percent of your 2000 Calorie daily food intake is left for broccoli, beans, beef, etc.?

Accepted Answer

A)   53%
B)   47%
C)   27%
D)   11%
E)   0%F) A) and B)
G) All of the above

Question 19

Which one of the following equations represents the formation reaction of CH3OH(l) ?

Accepted Answer

A)   C(g)  + 2H2(g)  + 3OH(l) ? 
A)   C(g)  + 2H2(g)  +   O2 (g)   CH3OH(l)  
B)   C(g)  + 4H(g)  + O(g)   CH3OH(l)  
C)   C(graphite)  + 4H(g)  + O(g)   CH3OH(l)  
D)   C(diamond)  + 4H(g)  + O(g)   CH3OH(l)  
E)   C(graphite)  + 2H2(g)  +   O2(g)   CH3OH(l) " class="answers-bank-image d-inline" rel="preload" > O2 (g)   CH3OH(l) 
B)   C(g)  + 4H(g)  + O(g)   CH3OH(l) 
C)   C(graphite)  + 4H(g)  + O(g)   CH3OH(l) 
D)   C(diamond)  + 4H(g)  + O(g)   CH3OH(l) 
E)   C(graphite)  + 2H2(g)  + 3OH(l) ? 
A)   C(g)  + 2H2(g)  +   O2 (g)   CH3OH(l)  
B)   C(g)  + 4H(g)  + O(g)   CH3OH(l)  
C)   C(graphite)  + 4H(g)  + O(g)   CH3OH(l)  
D)   C(diamond)  + 4H(g)  + O(g)   CH3OH(l)  
E)   C(graphite)  + 2H2(g)  +   O2(g)   CH3OH(l) " class="answers-bank-image d-inline" rel="preload" > O2(g)   CH3OH(l) F) B) and D)
G) C) and E)

Question 20

The combustion of glucose (C6H12O6)  with oxygen gas produces carbon dioxide and water. This process releases 2803 kJ per mole of glucose. When 3.00 mol of oxygen react in this way with glucose, what is the energy release in kcal? (Hint: Write a balanced equation for the combustion process.)

Accepted Answer

A)   223.5 kcal
B)   335.3 kcal
C)   1402 kcal
D)   2012 kcal
E)   5858 kcalF) C) and E)
G) None of the above

Exam 6: Thermochemistry: Energy Flow and Chemical Change

A 275-g sample of nickel at 100.0°C is placed in 100.0 mL of water at 22.0°C. What is the final temperature of the water? Assume that no heat is lost to or gained from the surroundings. Specific heat capacity of nickel = 0.444 J/(g·K)

Correct Answer
verified

Benzene is a starting material in the synthesis of nylon fibers and polystyrene (styrofoam) . Its specific heat capacity is 1.74 J/(g·K) . If 16.7 kJ of energy is absorbed by a 225-g sample of benzene at 20.0°C, what is its final temperature?

Correct Answer
verified

The standard heat (enthalpy) of formation of graphite is zero.

Correct Answer
verified

The standard state of a substance in aqueous solution is a 1 M solution.

Correct Answer
verified

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide. 4NH₃(g) + 5O₂(g)  4NO(g) + 6H₂O(g) Calculate H°_rxn for this reaction. H°_f [NH₃(g) ] = -45.9 kJ/mol; H°_f [NO(g) ] = 90.3 kJ/mol; H°_f [H₂O(g) ] = -241.8 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, E, is 61.2 kJ, what is the final value of E?

Correct Answer
verified

Correct Answer
verified

a. State Hess's Law. b. Use the H° data given below to calculate H° for the reaction:

Correct Answer
verified
a. The enthalpy change for an ...
View Answer

a. Write a balanced equation for the combustion of benzene, C₆H₆(l) in oxygen. b. The standard heat of combustion of benzene is -3271 kJ/mol. Calculate its standard heat of formation, H°_f , given the data: H°_f [CO₂(g)] = -394 kJ; H°_f [H₂O(l)] = -286 kJ

Correct Answer
verified
a. C₆H₆(l) + 7.5O₂(g) F1...
View Answer

Which of the following is not a state function?

Correct Answer
verified

Your favorite candy bar, Gummy Beakers, contains 1.2 × 10⁶ J of energy while your favorite soft drink, Bolt, contains 6.7 × 10⁵ J. If you eat two packs of Gummy Beakers a day and drink 3 cans of Bolt, what percent of your 2000 Calorie daily food intake is left for broccoli, beans, beef, etc.?

Correct Answer
verified

Use Hess's Law to calculate the enthalpy change for the reaction WO₃(s) + 3H₂(g)  W(s) + 3H₂O(g) From the following data: 2W(s) + 3O₂(g)  2WO₃(s) H = -1685.4 kJ 2H₂(g) + O₂(g)  2H₂O(g) H = -477.84 kJ

Correct Answer
verified

Natural gas, or methane, is an important fuel. Combustion of one mole of methane releases 802.3 kilojoules of energy. How much energy does that represent in kilocalories?

Correct Answer
verified

Which one of the following equations represents the formation reaction of CH₃OH(l) ?

Correct Answer
verified

For all processes, both q and E will have the same sign.

Correct Answer
verified

What is the final temperature when 20.0 g of water at 25°C is mixed with 30.0 g of water at 80°C?

Correct Answer
verified

Correct Answer
verified
a. 5.5 × 1...
View Answer

Calculate the H°_rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide. H°_f [CaCO₃(s) ] = -1206.9 kJ/mol; H°_f [CaO(s) ] = -635.1 kJ/mol; H°_f [CO₂(g) ] = -393.5 kJ/mol CaCO₃(s)  CaO(s) + CO₂(g)

Correct Answer
verified

The combustion of glucose (C₆H₁₂O₆) with oxygen gas produces carbon dioxide and water. This process releases 2803 kJ per mole of glucose. When 3.00 mol of oxygen react in this way with glucose, what is the energy release in kcal? (Hint: Write a balanced equation for the combustion process.)

Correct Answer
verified

Which one of the following is not a correct formation reaction? (products are correct)

Correct Answer
verified

Exam 6: Thermochemistry: Energy Flow and Chemical Change

A 275-g sample of nickel at 100.0°C is placed in 100.0 mL of water at 22.0°C. What is the final temperature of the water? Assume that no heat is lost to or gained from the surroundings. Specific heat capacity of nickel = 0.444 J/(g·K)

Correct AnswerverifiedShow Answer

Benzene is a starting material in the synthesis of nylon fibers and polystyrene (styrofoam) . Its specific heat capacity is 1.74 J/(g·K) . If 16.7 kJ of energy is absorbed by a 225-g sample of benzene at 20.0°C, what is its final temperature?

Correct AnswerverifiedShow Answer

The standard heat (enthalpy) of formation of graphite is zero.

Correct AnswerverifiedShow Answer

The standard state of a substance in aqueous solution is a 1 M solution.

Correct AnswerverifiedShow Answer

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide. 4NH3(g) + 5O2(g)  4NO(g) + 6H2O(g) Calculate H°rxn for this reaction. H°f [NH3(g) ] = -45.9 kJ/mol; H°f [NO(g) ] = 90.3 kJ/mol; H°f [H2O(g) ] = -241.8 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, E, is 61.2 kJ, what is the final value of E?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

a. State Hess's Law. b. Use the H° data given below to calculate H° for the reaction:

Correct Answerverifieda. The enthalpy change for an ...View AnswerShow Answer

a. Write a balanced equation for the combustion of benzene, C6H6(l) in oxygen. b. The standard heat of combustion of benzene is -3271 kJ/mol. Calculate its standard heat of formation, H°f , given the data: H°f [CO2(g)] = -394 kJ; H°f [H2O(l)] = -286 kJ

Correct Answerverifieda. C6H6(l) + 7.5O2(g) F1...View AnswerShow Answer

Which of the following is not a state function?

Correct AnswerverifiedShow Answer

Your favorite candy bar, Gummy Beakers, contains 1.2 × 106 J of energy while your favorite soft drink, Bolt, contains 6.7 × 105 J. If you eat two packs of Gummy Beakers a day and drink 3 cans of Bolt, what percent of your 2000 Calorie daily food intake is left for broccoli, beans, beef, etc.?

Correct AnswerverifiedShow Answer

Use Hess's Law to calculate the enthalpy change for the reaction WO3(s) + 3H2(g)  W(s) + 3H2O(g) From the following data: 2W(s) + 3O2(g)  2WO3(s) H = -1685.4 kJ 2H2(g) + O2(g)  2H2O(g) H = -477.84 kJ

Correct AnswerverifiedShow Answer

Natural gas, or methane, is an important fuel. Combustion of one mole of methane releases 802.3 kilojoules of energy. How much energy does that represent in kilocalories?

Correct AnswerverifiedShow Answer

Which one of the following equations represents the formation reaction of CH3OH(l) ?

Correct AnswerverifiedShow Answer

For all processes, both q and E will have the same sign.

Correct AnswerverifiedShow Answer

What is the final temperature when 20.0 g of water at 25°C is mixed with 30.0 g of water at 80°C?

Correct AnswerverifiedShow Answer

Correct Answerverifieda. 5.5 × 1...View AnswerShow Answer

Calculate the H°rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide. H°f [CaCO3(s) ] = -1206.9 kJ/mol; H°f [CaO(s) ] = -635.1 kJ/mol; H°f [CO2(g) ] = -393.5 kJ/mol CaCO3(s)  CaO(s) + CO2(g)

Correct AnswerverifiedShow Answer

The combustion of glucose (C6H12O6) with oxygen gas produces carbon dioxide and water. This process releases 2803 kJ per mole of glucose. When 3.00 mol of oxygen react in this way with glucose, what is the energy release in kcal? (Hint: Write a balanced equation for the combustion process.)

Correct AnswerverifiedShow Answer

Which one of the following is not a correct formation reaction? (products are correct)

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

An important step in the synthesis of nitric acid is the conversion of ammonia to nitric oxide. 4NH₃(g) + 5O₂(g)  4NO(g) + 6H₂O(g) Calculate H°_rxn for this reaction. H°_f [NH₃(g) ] = -45.9 kJ/mol; H°_f [NO(g) ] = 90.3 kJ/mol; H°_f [H₂O(g) ] = -241.8 kJ/mol

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified
a. The enthalpy change for an ...
View Answer

a. Write a balanced equation for the combustion of benzene, C₆H₆(l) in oxygen. b. The standard heat of combustion of benzene is -3271 kJ/mol. Calculate its standard heat of formation, H°_f , given the data: H°_f [CO₂(g)] = -394 kJ; H°_f [H₂O(l)] = -286 kJ

Correct Answer
verified
a. C₆H₆(l) + 7.5O₂(g) F1...
View Answer

Correct Answer
verified

Your favorite candy bar, Gummy Beakers, contains 1.2 × 10⁶ J of energy while your favorite soft drink, Bolt, contains 6.7 × 10⁵ J. If you eat two packs of Gummy Beakers a day and drink 3 cans of Bolt, what percent of your 2000 Calorie daily food intake is left for broccoli, beans, beef, etc.?

Correct Answer
verified

Use Hess's Law to calculate the enthalpy change for the reaction WO₃(s) + 3H₂(g)  W(s) + 3H₂O(g) From the following data: 2W(s) + 3O₂(g)  2WO₃(s) H = -1685.4 kJ 2H₂(g) + O₂(g)  2H₂O(g) H = -477.84 kJ

Correct Answer
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Correct Answer
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Which one of the following equations represents the formation reaction of CH₃OH(l) ?

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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a. 5.5 × 1...
View Answer

Calculate the H°_rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide. H°_f [CaCO₃(s) ] = -1206.9 kJ/mol; H°_f [CaO(s) ] = -635.1 kJ/mol; H°_f [CO₂(g) ] = -393.5 kJ/mol CaCO₃(s)  CaO(s) + CO₂(g)

Correct Answer
verified

The combustion of glucose (C₆H₁₂O₆) with oxygen gas produces carbon dioxide and water. This process releases 2803 kJ per mole of glucose. When 3.00 mol of oxygen react in this way with glucose, what is the energy release in kcal? (Hint: Write a balanced equation for the combustion process.)

Correct Answer
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Correct Answer
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