Question 1

An ideal gas (the system) is contained in a flexible balloon at a pressure of 1 atm and is initially at a temperature of 20.°C.The surrounding air is at the same pressure,but its temperature is 25°C.When the system has equilibrated with its surroundings,both systems and surroundings are at 25°C and 1 atm.In changing from the initial to the final state,which one of the following relationships regarding the system is correct?

Accepted Answer

A)  ( Δ\DeltaΔ E 
B)  ( Δ\DeltaΔ E = 0) 
C)  ( Δ\DeltaΔ H = 0) 
D)  w > 0
E)  q > 0 F) B) and D)
G) A) and D)

Question 2

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

Question 3

Calculate the  Δ\DeltaΔ H°rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide.
 Δ\DeltaΔ H°f [CaCO3(s) ] = -1206.9 kJ/mol; Δ\DeltaΔ H°f [CaO(s) ] = -635.1 kJ/mol; Δ\DeltaΔ H°f [CO2(g) ] = -393.5 kJ/mol
CaCO3(s)  →	o→ 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 kJ F) A) and E)
G) None of the above

Question 4

Which one of the following is a correct formation reaction?

Accepted Answer

A)  C(diamond)   →	o→  C(graphite) 
B)  H2(g) + O(g)   →	o→  H2O(l) 
C)  C(graphite) + 4H(g)   →	o→ CH4(g) 
D)  6C(graphite) + 6H2O(s)   →	o→  C6H12O6(s) 
E)  2C(graphite) + 3H2(g) +2(g) + O(g)   	o  H2O(l)  
C)  C(graphite) + 4H(g)   	o CH4(g)  
D)  6C(graphite) + 6H2O(s)   	o  C6H12O6(s)  
E)  2C(graphite) + 3H2(g) +   O2(g)   	o  C2H5OH(l)  " class="answers-bank-image d-inline" rel="preload" >O2(g)   →	o→  C2H5OH(l)  F) B) and C)
G) B) and E)

Question 5

a.A gas sample absorbs 53 kJ of heat and does 18 kJ of work.Calculate the change in its internal energy.
b.A system expands against a constant pressure of 1.50 atm,from an initial volume of 1.00 L to a final volume of 10.0 L.Calculate the work (w)involved in this process,in kJ.

Accepted Answer

a.<img  loading="lazy" src="/assets/images/blured-textbook.svg" class="d-inline m-1" alt="blured image" width="139" height="30">E = 35 k...

Question 6

Which one of the following relationships is always correct?

Accepted Answer

A)  potential energy + kinetic energy = constant
B)  E = q + w
C)  ( Δ\DeltaΔ E =  Δ\DeltaΔ H - P Δ\DeltaΔ V) 
D)  H = E + PV
E)  ( Δ\DeltaΔ H = qv)  F) C) and E)
G) A) and C)

Question 7

Although internal energy (E)is more fundamental and conceptually easier than enthalpy (H),in most chemical applications $\Delta$H is more relevant and useful than $\Delta$E.Why?

Accepted Answer

Most chemical processes of interest occu...

Question 8

Standard heats (enthalpies)of formation of compounds,$\Delta$H°f ,may be positive or negative.

Accepted Answer

A) True 
 B)False

Question 9

When Karl Kaveman adds chilled grog to his new granite mug,he removes 10.9 kJ of energy from the mug.If it has a mass of 625 g and was at 25°C,what is its new temperature? Specific heat capacity of granite = 0.79 J/(g·K)

Accepted Answer

A)  3°C
B)  14°C
C)  22°C
D)  47°C
E)  None of these choices is correct.F) All of the above
G) A) and B)

Question 10

Cold packs,whose temperatures are lowered when ammonium nitrate dissolves in water,are carried by athletic trainers when transporting ice is not possible.Which of the following is true of this reaction?

Accepted Answer

A)  ( Δ\DeltaΔ H 
B)  ( Δ\DeltaΔ H > 0,process is exothermic) 
C)  ( Δ\DeltaΔ H 
D)  ( Δ\DeltaΔ H > 0,process is endothermic) 
E)  ( Δ\DeltaΔ H = 0,since cold packs are sealed)  F) C) and D)
G) A) and E)

Question 11

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

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 these choices is correct.F) C) and E)
G) B) and D)

Exam 6: Thermochemistry: Energy Flow and Chemical Change

Although internal energy (E)is more fundamental and conceptually easier than enthalpy (H),in most chemical applications $\Delta$ H is more relevant and useful than $\Delta$ E.Why?

Correct Answer
verified
Most chemical processes of interest occu...
View Answer

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

Correct Answer
verified

Correct Answer
verified

Standard heats (enthalpies)of formation of compounds, $\Delta$ H°_f ,may be positive or negative.

Correct Answer
verified

Which one of the following relationships is always correct?

Correct Answer
verified

Cold packs,whose temperatures are lowered when ammonium nitrate dissolves in water,are carried by athletic trainers when transporting ice is not possible.Which of the following is true of this reaction?

Correct Answer
verified

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 What is the enthalpy change if 3.8 mol of calcium carbonate is formed?

Correct Answer
verified

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

Correct Answer
verified

When Karl Kaveman adds chilled grog to his new granite mug,he removes 10.9 kJ of energy from the mug.If it has a mass of 625 g and was at 25°C,what is its new temperature? Specific heat capacity of granite = 0.79 J/(g·K)

Correct Answer
verified

Which one of the following is a correct formation reaction?

Correct Answer
verified

a.A gas sample absorbs 53 kJ of heat and does 18 kJ of work.Calculate the change in its internal energy. b.A system expands against a constant pressure of 1.50 atm,from an initial volume of 1.00 L to a final volume of 10.0 L.Calculate the work (w)involved in this process,in kJ.

Correct Answer
verified
a.E = 35 k...
View Answer

Exam 6: Thermochemistry: Energy Flow and Chemical Change

Although internal energy (E)is more fundamental and conceptually easier than enthalpy (H),in most chemical applications Δ\DeltaΔ H is more relevant and useful than Δ\DeltaΔ E.Why?

Correct AnswerverifiedMost chemical processes of interest occu...View AnswerShow Answer

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

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Standard heats (enthalpies)of formation of compounds, Δ\DeltaΔ H°f ,may be positive or negative.

Correct AnswerverifiedShow Answer

Which one of the following relationships is always correct?

Correct AnswerverifiedShow Answer

Cold packs,whose temperatures are lowered when ammonium nitrate dissolves in water,are carried by athletic trainers when transporting ice is not possible.Which of the following is true of this reaction?

Correct AnswerverifiedShow Answer

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 What is the enthalpy change if 3.8 mol of calcium carbonate is formed?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

When Karl Kaveman adds chilled grog to his new granite mug,he removes 10.9 kJ of energy from the mug.If it has a mass of 625 g and was at 25°C,what is its new temperature? Specific heat capacity of granite = 0.79 J/(g·K)

Correct AnswerverifiedShow Answer

Which one of the following is a correct formation reaction?

Correct AnswerverifiedShow Answer

a.A gas sample absorbs 53 kJ of heat and does 18 kJ of work.Calculate the change in its internal energy. b.A system expands against a constant pressure of 1.50 atm,from an initial volume of 1.00 L to a final volume of 10.0 L.Calculate the work (w)involved in this process,in kJ.

Correct Answerverifieda.E = 35 k...View AnswerShow Answer

Although internal energy (E)is more fundamental and conceptually easier than enthalpy (H),in most chemical applications $\Delta$ H is more relevant and useful than $\Delta$ E.Why?

Correct Answer
verified
Most chemical processes of interest occu...
View Answer

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

Correct Answer
verified

Correct Answer
verified

Standard heats (enthalpies)of formation of compounds, $\Delta$ H°_f ,may be positive or negative.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
a.E = 35 k...
View Answer