Question 1

The figure represents the spontaneous deposition of iodine in which iodine vapor,I2(g),becomes crystalline iodine solid I2(s): I2(g): → I2(s).What are the signs (+ or -)of ΔH,ΔS,and ΔG for this process?

Accepted Answer

A) ΔH = +,ΔS = +,ΔG = + 
B) ΔH = +,ΔS = +,ΔG = - 
C) ΔH = -,ΔS = -,ΔG = + 
D) ΔH = -,ΔS = -,ΔG = -

Question 2

At high temperatures boron carbide vaporizes according to the equation
B4C(s)⇌ 4 B(g)+ C(s)
Which equation describes the relationship between ΔG° and ΔG for this reaction?

Accepted Answer

A) ΔG = ΔG° + R T ln (pB ∙ [C]/[B4C]) 
B) ΔG = ΔG° + R T ln pB 
C) ΔG = ΔG° + 4 R T ln pB 
D) ΔG = ΔG° - 4 R T ln pB

Question 3

For the reaction N₂(g)+2 O₂(g)→ 2 NO₂(g),ΔH° = 66.4 kJ/mol and ΔS° = -121.5 J/K.ΔS_total for this reaction is ________ J/K,and the reaction is ________ (spontaneous,nonspontaneous)at 25°C.

Accepted Answer

The answer of For the reaction N₂(g)+2 O₂(g)→ 2 NO₂(g),ΔH°...

Question 4

In figure (1)below oxygen molecules,represented by unshaded spheres,and chlorine molecules,represented by shaded spheres,are in separate compartments.Figure (2)shows the equilibrium state of the system after the stopcock separating the two compartments is opened.Assuming the oxygen and the chlorine behave as ideal gases,what are the signs (+,-,or 0)of ΔH,ΔS,and ΔG for this process?

Accepted Answer

A) ΔH = +,ΔS = -,ΔG = + 
B) ΔH = 0,ΔS = +,ΔG = - 
C) ΔH = 0,ΔS = -,ΔG = + 
D) ΔH = -,ΔS = +,ΔG = -

Question 5

Which statement is true about the formation of CaCO3(s)from CaO(s)and CO2(g)at 1.00 atm?
CaO(s)+ CO2(g)→ CaCO3(s)ΔH° = -178.7 kJ and ΔS° = -150.4 J/K

Accepted Answer

A) The reaction is spontaneous at all temperatures. 
B) The reaction is spontaneous at high temperatures. 
C) The reaction is spontaneous at low temperatures. 
D) The reaction is not spontaneous at any temperature.

Question 6

When equilibrium is reached at constant temperature and pressure,

Accepted Answer

A) Q = 1. 
B) ΔG° = 0. 
C) S is maximized. 
D) G is minimized.

Question 7

Other than only PV work,what reaction conditions must be satisfied for the sign of ΔG to be used as a criterion for spontaneity?

Accepted Answer

A) constant volume and pressure 
B) constant temperature and pressure 
C) constant temperature and volume 
D) constant volume only

Question 8

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. S(s,rhombic)+ O₂(g)→ SO₂(g) 31.8 205.0 248.1

Accepted Answer

The answer of Standard molar entropies,S°,in J/Kmol,are given below each...

Question 9

The entropy of water at 25° is ________ than the entropy of water at 35°C.

Accepted Answer

The answer of The entropy of water at 25° is...

Question 10

According to the second law of thermodynamics,all reactions proceed spontaneously in the direction that increases the entropy of the

Accepted Answer

A) surroundings. 
B) system. 
C) system - surroundings 
D) system + surroundings

Question 11

The most commonly used white pigment is titanium white,which is titanium(IV)oxide,TiO₂.Titanium white can be formed from TiCl₄ as shown in the reaction below. TiCl₄(l)+ 2 H₂O(l)→ TiO₂(s)+ 4 HCl(g) If ΔH° = 61.9 kJ/mol and ΔS° = 405.4 J/K,what are ΔS_surr and ΔS_total for this reaction at 25°C?

Accepted Answer

The answer of The most commonly used white pigment is...

Question 12

Which of the following processes is spontaneous?

Accepted Answer

A) a mixture of two gases separating into pure compounds 
B) reaction of sodium with oxygen 
C) precipitation of solute from a saturated solution 
D) water flowing uphill

Question 13

The entropy change associated with the expansion of one mole of an ideal gas from an initial volume of Vi to a final volume of Vf at constant temperature is given by the equation,ΔS = R ln (Vf/Vi).What is the entropy change associated with the expansion of three moles of an ideal gas from an initial volume of Vi to a final volume of Vf at constant temperature?

Accepted Answer

A) ΔS = R ln (Vf/Vi) 
B) ΔS = 3 mol × R ln (Vf/Vi) 
C) ΔS = R ln (Vf × 23/Vi) 
D) ΔS = R ln (Vf × 3!/Vi)

Question 14

Consider the reaction 2A(g)⇌ AS1U1B12S1U1B0(g).The following pictures represent two possible initial states and the equilibrium state of the system. 
-For initial state 1 what is the relationship between the reaction quotient,Qp,and the equilibrium constant,Kp?

Accepted Answer

A) Qp p 
B) Qp = Kp = 1 
C) Qp = Kp ≠ 1 
D) Qp > Kp

Question 15

A reaction has ΔG° = + 21.5 kJ/mol,ΔH° = + 25.0 kJ/mol,and ΔS° = + 15.0 J/mol∙K can become spontaneous at a temperature of ________ K.

Accepted Answer

The answer of A reaction has ΔG° = + 21.5...

Question 16

Calculate the standard free energy change at 25°C for the reaction
2 NO(g)+ O2(g)→ 2 NO2(g).

Accepted Answer

A) -4.7 kJ 
B) -72.6 kJ 
C) -157.8 kJ 
D) -532.6 kJ

Question 17

Which of the following statements is not true?

Accepted Answer

A) The reverse of a spontaneous reaction is always nonspontaneous. 
B) A spontaneous process always moves toward equilibrium. 
C) A nonspontaneous process cannot be caused to occur. 
D) A highly spontaneous process need not occur rapidly.

Question 18

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. 2 SO₂(g)+ O₂(g)→ 2 SO₃(g) 248.1 205.0 256.6

Accepted Answer

The answer of Standard molar entropies,S°,in J/Kmol,are given below each...

Question 19

A 1.0 mole sample of gas at STP has a ________ entropy than 1.0 mole of gas at 273 K and
835 mm Hg.

Accepted Answer

The answer of A 1.0 mole sample of gas at...

Question 20

Standard molar entropies,S°,in J/K∙mol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. CH₄(g)+ 2 O₂(g)→ CO₂(g)+ 2 H₂O(l) 186.2 205.0 213.6 69.9

Accepted Answer

The answer of Standard molar entropies,S°,in J/K∙mol,are given below each...

Exam 16: Thermodynamics: Entropy, free Energy, and Equilibrium

The figure represents the spontaneous deposition of iodine in which iodine vapor,I₂(g) ,becomes crystalline iodine solid I₂(s) : I₂(g) : → I₂(s) .What are the signs (+ or -) of ΔH,ΔS,and ΔG for this process?

At high temperatures boron carbide vaporizes according to the equation B₄C(s) ⇌ 4 B(g) + C(s) Which equation describes the relationship between ΔG° and ΔG for this reaction?

For the reaction N₂(g)+2 O₂(g)→ 2 NO₂(g),ΔH° = 66.4 kJ/mol and ΔS° = -121.5 J/K.ΔS_total for this reaction is J/K,and the reaction is (spontaneous,nonspontaneous)at 25°C.

Which statement is true about the formation of CaCO₃(s) from CaO(s) and CO₂(g) at 1.00 atm? CaO(s) + CO₂(g) → CaCO₃(s) ΔH° = -178.7 kJ and ΔS° = -150.4 J/K

When equilibrium is reached at constant temperature and pressure,

Other than only PV work,what reaction conditions must be satisfied for the sign of ΔG to be used as a criterion for spontaneity?

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. S(s,rhombic)+ O₂(g)→ SO₂(g) 31.8 205.0 248.1

The entropy of water at 25° is ________ than the entropy of water at 35°C.

According to the second law of thermodynamics,all reactions proceed spontaneously in the direction that increases the entropy of the

Which of the following processes is spontaneous?

Consider the reaction 2A(g) ⇌ A₂(g) .The following pictures represent two possible initial states and the equilibrium state of the system. -For initial state 1 what is the relationship between the reaction quotient,Q_p,and the equilibrium constant,K_p?

A reaction has ΔG° = + 21.5 kJ/mol,ΔH° = + 25.0 kJ/mol,and ΔS° = + 15.0 J/mol∙K can become spontaneous at a temperature of ________ K.

Calculate the standard free energy change at 25°C for the reaction 2 NO(g) + O₂(g) → 2 NO₂(g) .

Which of the following statements is not true?

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. 2 SO₂(g)+ O₂(g)→ 2 SO₃(g) 248.1 205.0 256.6

A 1.0 mole sample of gas at STP has a ________ entropy than 1.0 mole of gas at 273 K and 835 mm Hg.

Standard molar entropies,S°,in J/K∙mol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. CH₄(g)+ 2 O₂(g)→ CO₂(g)+ 2 H₂O(l) 186.2 205.0 213.6 69.9

Exam 16: Thermodynamics: Entropy, free Energy, and Equilibrium

The figure represents the spontaneous deposition of iodine in which iodine vapor,I2(g) ,becomes crystalline iodine solid I2(s) : I2(g) : → I2(s) .What are the signs (+ or -) of ΔH,ΔS,and ΔG for this process?

At high temperatures boron carbide vaporizes according to the equation B4C(s) ⇌ 4 B(g) + C(s) Which equation describes the relationship between ΔG° and ΔG for this reaction?

For the reaction N2(g)+2 O2(g)→ 2 NO2(g),ΔH° = 66.4 kJ/mol and ΔS° = -121.5 J/K.ΔStotal for this reaction is ________ J/K,and the reaction is ________ (spontaneous,nonspontaneous)at 25°C.

Which statement is true about the formation of CaCO3(s) from CaO(s) and CO2(g) at 1.00 atm? CaO(s) + CO2(g) → CaCO3(s) ΔH° = -178.7 kJ and ΔS° = -150.4 J/K

When equilibrium is reached at constant temperature and pressure,

Other than only PV work,what reaction conditions must be satisfied for the sign of ΔG to be used as a criterion for spontaneity?

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. S(s,rhombic)+ O2(g)→ SO2(g) 31.8 205.0 248.1

The entropy of water at 25° is ________ than the entropy of water at 35°C.

According to the second law of thermodynamics,all reactions proceed spontaneously in the direction that increases the entropy of the

Which of the following processes is spontaneous?

Consider the reaction 2A(g) ⇌ A2(g) .The following pictures represent two possible initial states and the equilibrium state of the system. -For initial state 1 what is the relationship between the reaction quotient,Qp,and the equilibrium constant,Kp?

A reaction has ΔG° = + 21.5 kJ/mol,ΔH° = + 25.0 kJ/mol,and ΔS° = + 15.0 J/mol∙K can become spontaneous at a temperature of ________ K.

Calculate the standard free energy change at 25°C for the reaction 2 NO(g) + O2(g) → 2 NO2(g) .

Which of the following statements is not true?

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. 2 SO2(g)+ O2(g)→ 2 SO3(g) 248.1 205.0 256.6

A 1.0 mole sample of gas at STP has a ________ entropy than 1.0 mole of gas at 273 K and 835 mm Hg.

Standard molar entropies,S°,in J/K∙mol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. CH4(g)+ 2 O2(g)→ CO2(g)+ 2 H2O(l) 186.2 205.0 213.6 69.9

The figure represents the spontaneous deposition of iodine in which iodine vapor,I₂(g) ,becomes crystalline iodine solid I₂(s) : I₂(g) : → I₂(s) .What are the signs (+ or -) of ΔH,ΔS,and ΔG for this process?

At high temperatures boron carbide vaporizes according to the equation B₄C(s) ⇌ 4 B(g) + C(s) Which equation describes the relationship between ΔG° and ΔG for this reaction?

For the reaction N₂(g)+2 O₂(g)→ 2 NO₂(g),ΔH° = 66.4 kJ/mol and ΔS° = -121.5 J/K.ΔS_total for this reaction is J/K,and the reaction is (spontaneous,nonspontaneous)at 25°C.

Which statement is true about the formation of CaCO₃(s) from CaO(s) and CO₂(g) at 1.00 atm? CaO(s) + CO₂(g) → CaCO₃(s) ΔH° = -178.7 kJ and ΔS° = -150.4 J/K

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. S(s,rhombic)+ O₂(g)→ SO₂(g) 31.8 205.0 248.1

Consider the reaction 2A(g) ⇌ A₂(g) .The following pictures represent two possible initial states and the equilibrium state of the system. -For initial state 1 what is the relationship between the reaction quotient,Q_p,and the equilibrium constant,K_p?

Calculate the standard free energy change at 25°C for the reaction 2 NO(g) + O₂(g) → 2 NO₂(g) .

Standard molar entropies,S°,in J/Kmol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. 2 SO₂(g)+ O₂(g)→ 2 SO₃(g) 248.1 205.0 256.6

Standard molar entropies,S°,in J/K∙mol,are given below each reactant and product in the reaction shown below.The standard entropy of reaction,ΔS°,for this reaction is ________ J/K. CH₄(g)+ 2 O₂(g)→ CO₂(g)+ 2 H₂O(l) 186.2 205.0 213.6 69.9