Question 1

An important reagent in organic chemistry is thionyl chloride, SOCl2. One synthetic route would be to react SO2 with HCl in the gas phase to produce SOCl2 and water. What is the entropy change for this reaction? (J/K•mole SOCl2)? (S? = 309.7(SOCl2), 248.2(SO2), 186.9(HCl), 188.8(H2O) in J/K•mole)

Accepted Answer

A)  -123 
B)  123 
C)  -246 
D)  -146 
E)  61.5

Question 2

Predict the direction of change based on the entropy changes in the system and in the surroundings.

Accepted Answer

The answer of Predict the direction of change based on...

Question 3

Isomerization of hydrocarbons is important in the refining of petroleum. A simple example is that of butane, which has only two isomers:   Which of the following statements is most correct?

Accepted Answer

A)  At standard temperatures, n-butane is the preferred isomer. 
B)  At temperatures less than 450, n-butane is the preferred isomer. 
C)  At temperatures greater than 450ºK, n-butane is the preferred isomer. 
D)  At ambient temperatures, a sample of n-butane and isobutene which was at equilibrium would contain barely any butane. 
E)  A 1:1 mixture of butane and isobutane is at equilibrium at room temperature.

Question 4

A child plays with a deck of cards and leaves the room. You politely pick up and organize the cards. Which of the following is true during the action of organizing the cards?

Accepted Answer

A)  You become more ordered. 
B)  The universe becomes more ordered. 
C)  The deck of cards becomes more disordered. 
D)  You become more disordered. 
E)  The ordering of a deck of cards is spontaneous.

Question 5

What is the reaction quotient for the following unbalanced cell reaction?Ba(OH)₂.08H₂O_(s) + NH₄NO_3(s) $\rightarrow$ Ba(NO₃)_2(s)+ H₂O_(l) + NH₃₍_aq₎

Accepted Answer

The answer of What is the reaction quotient for the...

Question 6

Which of the following selections has the molecules arranged in order of increasing standard entropy? (One mole of each substance is being compared.)

Accepted Answer

A)  C(graphite), C60(s), C(diamond) 
B)  Si(s), P4(s), S8(s) 
C)  C2H6(g), C2H4(g), CH4(g) 
D)  Polystyrene (made of 1000 monomer units), DNA (1000 base pairs), polyethylene (1000 monomer units) 
E)  CH4(g), C2H6(g), C2H4(g)

Question 7

Chemical energy stored in glucose can be used to convert ADP to ATP; under normal physiological conditions the process, shown below, is 38.3 % efficient: C₆H₁₂O₆+ 6O₂ + 36 ADP + 36 H₃PO₄ $\rightarrow$ 6CO₂ + 36 ATP + 42 H₂O $\Delta$G° = Given that the reaction: ADP + H₃PO₄ $\rightarrow$ ATP + H₂O requires 30.6 kJ mol^-1 determine $\Delta$G° for the reaction of glucose and ADP above.

Accepted Answer

The answer of Chemical energy stored in glucose can be...

Question 8

The process of storing energy for short term in the body is by making ATP. What type of bond is made or broken in this process?

Accepted Answer

A)  making of a phosphate ester (P-O-P) bond 
B)  breaking of a phosphate ester bond 
C)  addition of water to ADP 
D)  the forming of a C=O bond 
E)  the forming of a C=C bond

Question 9

One process water can undergo is dissociation, the equation for which is shown below:H2O (l) $\rarr$H+ (aq) + OH- (aq)As temperature increases to 90°C,

Accepted Answer

A)  there will be no shift in the position of equilibrium. 
B)  more reactants will be present at equilibrium. 
C)  the extent of dissociation will be less. 
D)  the extent of dissociation will be greater. 
E)  the water will vapourize rather than dissociate.

Question 10

Determine Gibb's Free Energy and if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. Ba(OH)₂.8H₂O_(s) + NH₄NO_3(s) $\rightarrow$Ba(NO₃)_2(s)+ H₂O_(l) + NH₃₍_aq₎

Accepted Answer

The answer of Determine Gibb's Free Energy and if the...

Question 11

An electric heater releases 1200 J of energy every second. How much does the entropy of the surroundings increase when the heater runs for 10 minutes in a room that is at 25°C?

Accepted Answer

The answer of An electric heater releases 1200 J of...

Question 12

Describe thermodynamically some representative energetic processes that operate in living organisms.

Accepted Answer

The answer of Describe thermodynamically some representative energetic processes that...

Question 13

Which of the following processes generate thermal pollution?
I. Hydroelectric generation of electricity
II. Nuclear generation of electricity
III. Coal powered generation of electricity
IV. Natural gas/oil powered generation of electricity
V. Wind farms

Accepted Answer

A)  all of the above 
B)  I, II, III, and IV 
C)  III and IV 
D)  II, III, IV and V 
E)  II, III, IV

Question 14

Determine if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. ($\Delta$G° = -857, SiO₂; 0, Si; 0, Al; -1582 kJ/mol) SiO_2(s) + Al_(s) $\rightarrow$Al₂O_3(s) + Si_(s)

Accepted Answer

The answer of Determine if the following unbalanced reaction is...

Question 15

A person exercises for 30 minutes and burns 800 kJ of free energy. How many moles of ATP (-30.6 kJ/mol) does this represent and based on 38% efficiency, how many grams of glucose were burned if 1 mole of glucose can make 36 ATPs?

Accepted Answer

The answer of A person exercises for 30 minutes and...

Question 16

Liquids composed of different molecules have different degrees of order. Compare the liquid phases of H₂S and H₂O and suggest which is more "ordered."

Accepted Answer

The answer of Liquids composed of different molecules have different...

Question 17

One of the more important industrial chemicals is hydrogen. One process for hydrogen production is called "steam reforming", in which hydrocarbons react with water to give hydrogen and CO. The equation of reaction for reforming methane is written below: CH₄ ₍_g₎ + H₂O ₍_g₎ $\rightarrow$CO ₍_g₎ + 3 H₂₍_g₎ a) Calculate the free energy change for this reaction at standard conditions. b) Estimate the temperature at which the process becomes spontaneous.

Accepted Answer

The answer of One of the more important industrial chemicals...

Question 18

Which of the following energy producing technologies has no effect on the environment?

Accepted Answer

A)  nuclear power 
B)  geothermal power 
C)  hydroelectric power 
D)  solar power 
E)  No energy producing technology is free from effects on the environment.

Question 19

A reaction will NEVER be spontaneous when

Accepted Answer

A)  $\Delta$G° > 0. 
B)  $\Delta$H° 0. 
C)  $\Delta$H° 0.

Question 20

What are the signs for the entropy change of the system and surroundings, respectively, for ethane burning, when the system is defined as ethane and oxygen?

Accepted Answer

A)  0 
C)  0, 0 
D)  >0, 0, >0

Exam 12: Spontaneity of Chemical Processes

Predict the direction of change based on the entropy changes in the system and in the surroundings.

Isomerization of hydrocarbons is important in the refining of petroleum. A simple example is that of butane, which has only two isomers: Which of the following statements is most correct?

A child plays with a deck of cards and leaves the room. You politely pick up and organize the cards. Which of the following is true during the action of organizing the cards?

What is the reaction quotient for the following unbalanced cell reaction?Ba(OH)₂.08H₂O_(s) + NH₄NO_3(s) $\rightarrow$ Ba(NO₃)_2(s)+ H₂O_(l) + NH₃₍_aq₎

Which of the following selections has the molecules arranged in order of increasing standard entropy? (One mole of each substance is being compared.)

The process of storing energy for short term in the body is by making ATP. What type of bond is made or broken in this process?

One process water can undergo is dissociation, the equation for which is shown below:H₂O₍_l₎ $\rarr$ H⁺ (aq) + OH^- (aq) As temperature increases to 90°C,

An electric heater releases 1200 J of energy every second. How much does the entropy of the surroundings increase when the heater runs for 10 minutes in a room that is at 25°C?

Describe thermodynamically some representative energetic processes that operate in living organisms.

Which of the following processes generate thermal pollution? I. Hydroelectric generation of electricity II. Nuclear generation of electricity III. Coal powered generation of electricity IV. Natural gas/oil powered generation of electricity V. Wind farms

Determine if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. ( $\Delta$ G° = -857, SiO₂; 0, Si; 0, Al; -1582 kJ/mol) SiO_2(s) + Al_(s) $\rightarrow$ Al₂O_3(s) + Si_(s)

A person exercises for 30 minutes and burns 800 kJ of free energy. How many moles of ATP (-30.6 kJ/mol) does this represent and based on 38% efficiency, how many grams of glucose were burned if 1 mole of glucose can make 36 ATPs?

Liquids composed of different molecules have different degrees of order. Compare the liquid phases of H₂S and H₂O and suggest which is more "ordered."

Which of the following energy producing technologies has no effect on the environment?

A reaction will NEVER be spontaneous when

What are the signs for the entropy change of the system and surroundings, respectively, for ethane burning, when the system is defined as ethane and oxygen?

Exam 12: Spontaneity of Chemical Processes

Predict the direction of change based on the entropy changes in the system and in the surroundings.

Isomerization of hydrocarbons is important in the refining of petroleum. A simple example is that of butane, which has only two isomers: Which of the following statements is most correct?

A child plays with a deck of cards and leaves the room. You politely pick up and organize the cards. Which of the following is true during the action of organizing the cards?

What is the reaction quotient for the following unbalanced cell reaction?Ba(OH)2.08H2O(s) + NH4NO3(s) →\rightarrow→ Ba(NO3)2(s) + H2O(l) + NH3(aq)

Which of the following selections has the molecules arranged in order of increasing standard entropy? (One mole of each substance is being compared.)

The process of storing energy for short term in the body is by making ATP. What type of bond is made or broken in this process?

One process water can undergo is dissociation, the equation for which is shown below:H2O (l) →\rarr→ H+ (aq) + OH- (aq) As temperature increases to 90°C,

Determine Gibb's Free Energy and if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. Ba(OH)2.8H2O(s) + NH4NO3(s) →\rightarrow→ Ba(NO3)2(s) + H2O(l) + NH3(aq)

An electric heater releases 1200 J of energy every second. How much does the entropy of the surroundings increase when the heater runs for 10 minutes in a room that is at 25°C?

Describe thermodynamically some representative energetic processes that operate in living organisms.

Which of the following processes generate thermal pollution? I. Hydroelectric generation of electricity II. Nuclear generation of electricity III. Coal powered generation of electricity IV. Natural gas/oil powered generation of electricity V. Wind farms

Determine if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. ( Δ\DeltaΔ G° = -857, SiO2; 0, Si; 0, Al; -1582 kJ/mol) SiO2(s) + Al(s) →\rightarrow→ Al2O3(s) + Si(s)

A person exercises for 30 minutes and burns 800 kJ of free energy. How many moles of ATP (-30.6 kJ/mol) does this represent and based on 38% efficiency, how many grams of glucose were burned if 1 mole of glucose can make 36 ATPs?

Liquids composed of different molecules have different degrees of order. Compare the liquid phases of H2S and H2O and suggest which is more "ordered."

Which of the following energy producing technologies has no effect on the environment?

A reaction will NEVER be spontaneous when

What are the signs for the entropy change of the system and surroundings, respectively, for ethane burning, when the system is defined as ethane and oxygen?

What is the reaction quotient for the following unbalanced cell reaction?Ba(OH)₂.08H₂O_(s) + NH₄NO_3(s) $\rightarrow$ Ba(NO₃)_2(s)+ H₂O_(l) + NH₃₍_aq₎

One process water can undergo is dissociation, the equation for which is shown below:H₂O₍_l₎ $\rarr$ H⁺ (aq) + OH^- (aq) As temperature increases to 90°C,

Determine if the following unbalanced reaction is spontaneous or non-spontaneous at standard conditions. ( $\Delta$ G° = -857, SiO₂; 0, Si; 0, Al; -1582 kJ/mol) SiO_2(s) + Al_(s) $\rightarrow$ Al₂O_3(s) + Si_(s)

Liquids composed of different molecules have different degrees of order. Compare the liquid phases of H₂S and H₂O and suggest which is more "ordered."