Ch. 17 - Chemical ThermodynamicsWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds
Additional Problems
Which of the following is always positive when a spontaneous process occurs? a. ΔSsystem b. ΔSsurroundings c. ΔSuniverse d. ΔHuniverse e. ΔHsurroundings    
What is true of the entropy of the universe? a. conserved b. continually decreasing c. continually increasing d. equal to zero e. equal to the energy, E
Physical processes, including chemical reactions, tend to go towards ________ entropy and _________ energy.  The answers in order are (a) lower, higher       (b) higher, lower       (c) lower, lower       (d) higher, higher
The Three Laws of Thermodynamics are as follows: 1. The total ____________ of the universe is constant. 2. The total ___________ of the universe increases for a spontaneous process. 3. The ____________ of a perfectly ordered crystal at 0 K is 0. The answers in order are (a) energy, energy, energy       (b) energy, entropy, energy       (c) entropy, energy, energy (d) entropy, energy, entropy     (e) energy, entropy, entropy
What is the second law of thermodynamics? (circle one) Change of entropy of the universe is conserved for a spontaneous process. Change of entropy of the system must be positive for a process to be spontaneous. Change of entropy of the universe must be positive for a spontaneous process. 
Entropy of the Universe will increase for all but which of the following? A)        H2O(s)  →  H2O(l)                       T = 233 K B)        H2O(l)   →  H2O(g)                      T = 379 K C)        CO2(g)  →  CO2(s)                       T = 298 K        D)        All of the Above E)        None of the above
A certain process has ΔSuniv > 0 at 25°C. What does one know about the prrocess? A) It is exothermic. B) It is endothermic. C) It is spontaneous at 25°C. D) It will move rapidly toward equilibrium. E) none of the above
Which of the following is true for a system at equilibrium? A) ΔS°sys = ΔS°surr B) ΔS°sys = - ΔS°surr C) ΔS°sys = ΔS°surr = 0 D) ΔS°univ > 0 E) None of these is a sufficient condition.
What term is given to the fact that the entropy of a perfect crystalline solid is zero at absolute zero? A) First Law of Thermodynamics B) Second Law of Thermodynamics C) Third Law of Thermodynamics D) crystalline lattice theory E) absolute crystallinity
The diagram below depicts the spontaneous sublimation of I2 (s) at 25°C and 1 atm: Accordingly, ΔSsys is ______ , ΔSsurr is _______, and ΔStotal is _______ for this transformation. (a) positive, positive, positive (b) positive, negative, positive (c) negative, positive, positive (d) positive, positive, negative (e) negative, positive, negative
The Entropy change of the Universe is A) Always equal to ΔSsurr B) Always the difference between the System and the Surroundings C) is only positive at higher temperatures D) is never negative E) is negative if ΔH is positive
What is the sign of ΔSuniv when a protein folds into its specific functional native structure starting from a random structure? A) zero B) negative C) positive D) It depends on the molecular weight of the protein. E) can only be determined if the ΔH of folding is known
What is the sign of ΔS univ for a biological system? A) zero B) negative C) positive D) It depends on the biological system.  
According to the Second Law of Thermodynamics, for any spontaneous process 1. The entropy of the system will decrease. 2. The total entropy of the combined system and surroundings will increase.  3. The entropy of the system will increase.  4. The entropy of the universe will tend toward zero. 5. Heat will be released into the surroundings increasing the entropy of the surroundings.
Which of the following are always true for spontaneous processes: I. ΔSuniverse ˃ 0 II. ΔSsystem ˃ 0 III. ΔSsystem + ΔSsurroundings ˃ 0 A. Only I B. Only II C. Only III D. I and II E. I and III
What are the signs of ∆Ssurr, ∆Ssys, and ∆Suniv, respectively, for a spontaneous endothermic reaction? 1. Cannot be predicted with certainty from the given information 2. −, +, +  3. +, +, + 4. −, +, − 5. +, −, −
Which of the following statements regarding the third law of thermodynamics is incorrect?    
Which of the following relationships must be true of any reaction at equilibrium? a) ∆Suniv = 0 b) ∆G ̊ = 0 c) ∆S ̊ = 0 d) Both a and b e) All of the above
Which of the following are always true for spontaneous processes:                         I.  ΔSuniverse > 0                         II.  ΔSsystem > 0                         III.  ΔSsystem + ΔSsurroundings > 0 A.  Only I        B.  Only II      C.  Only III     D.  I and II      E.  I and III
Vibrational and rotational motions in a water molecule.Describe another possible rotational motion for this molecule.
Indicate whether each statement is true or false.The third law of thermodynamics says that the entropy of a perfect, pure crystal at absolute zero increases with the mass of the crystal.
Indicate whether each statement is true or false."Translational motion" of molecules refers to their change in spatial location as a function of time.
Indicate whether each statement is true or false."Rotational" and "vibrational" motions contribute to the entropy in atomic gases like He and Xe.
Indicate whether each statement is true or false.The larger the number of atoms in a molecule, the more degrees of freedom of rotational and vibrational motion it likely has.
Indicate whether each statement is true or false.If you heat a gas such as CO2, you will increase its degrees of translational, rotational and vibrational motions.
State the third law of thermodynamics and explain its significance.
Entropy and the phases of water. The larger the number of possible microstates, the higher the entropy of the system.In which phase are water molecules least able to have rotational motion?
Can an argon atom undergo vibrational motion?
What is the molar entropy of a pure crystal at 0 K?
The rusting of iron is spontaneous and is accompanied by a decrease in the entropy of the system (the iron and oxygen).What can we conclude about the entropy change of the surroundings?
Indicate whether each statement is true or false.The second law of thermodynamics says that entropy is conserved.
Indicate whether each statement is true or false.If the entropy of the system increases during a reversible process, the entropy change of the surroundings must decrease by the same amount.
Indicate whether each statement is true or false.In a certain spontaneous process the system undergoes an entropy change of 4.2 J/K; therefore, the entropy change of the surroundings must be -4.2 J/K.
Do biological systems contradict the second law of thermodynamics? By taking energy from their surroundings and synthesizing large, complex biological molecules, plants and animals tend to concentrate energy, not disperse it.How can this be so?
Not all processes in which the system increases in entropy are spontaneous. How can this observation be consistent with the second law?
Provide the definition of the second law of thermodynamics.
How does the second law explain why heat travels from a substance at higher temperature to one at lower temperature?
What is entropy?
Which is NOT a consequence of the second law of thermodynamics?1. Heat spontaneously flows from a warmer body to a colder body.2. When a book falls, “ordered” kinetic energy is transformed into random heat energy3. Ice melts above OºC.4. During any naturally occurring process, the energy of the universe remains constant. 
For which of the following pure chemical substances (in the form of a perfect crystal) will S° = 0.00 J/mol.K at absolute zero? a) Cu b) O2 c) CuO2 d) Both a and b e) Both a and b and c
Define the following: a) Second Law of Thermodynamics b) triple point
The second law of thermodynamics states thata. the entropy of a perfect crystal is zero at 0K.b. the entropy of the universe is constant.c. the energy of the universe is increasing.d. the entropy of the universe is increasing.e. the energy of the universe is constant.
Which of the following are always true for a spontaneous process?I. ΔSsys > 0 II. ΔSsurr > 0 III. ΔSuniv > 0 IV. ΔGsys > 0a. Ib. IIc. IIId. I and IIIe. III and IV
Can an argon atom undergo vibrational motion?a. Yes.b. No.
The law states that a substance that is perfectly crystaline at 0 K has an entropy of zero. This law is called1. the second law of thermodynamics.2. the first law of thermodynamics.3. None of these4. the third law of thermodynamics.
Which of the following is always positive when a spontaneous process occurs? a. ΔSsystem b. ΔSsurroundings c. ΔSuniverse d. ΔHuniverse e. ΔHsurroundings
How does the process described in the above figure relate to the system shown in below?
Is the statement true or false? If false, correct it.(f) The energy of the universe is constant; the entropy of the universe decreases toward a minimum.
Is the statement true or false? If false, correct it.(g) All systems disperse their energy spontaneously.
Is the statement true or false? If false, correct it.(h) Both ΔSsys and ΔSsurr equal zero at equilibrium.
Indicate the sign of ΔSuniv for each process: 2H2(g) + O2 (g) → 2 H2O(l) at 298 K
Indicate the sign of ΔSuniv for each process: the electrolysis of H2O(l) to H2(g) and O2(g) at 298 K
Indicate the sign of ΔSuniv for each process: the growth of an oak tree from a little acorn
Which of the following processes is necessarily driven by an increase in the entropy of the surroundings?a. the condensation of waterb. the sublimation of dry icec. the freezing of water
Which process results in the increase in entropy of the universe?a) the cooling of a hot cup of coffee in room temperature airb) the evaporation of water from a desk at room temperaturec) the melting of snow above 0˚Cd) all of the above
Does the entropy of the surroundings increase for spontaneous processes?
Consider the reaction between nitrogen and oxygen gas to form dinitrogen monoxide: 2 N2(g) + O2(g)  →  2 N2O(g), ΔHrxn = + 163.2 kJDetermine the sign of the entropy change for the universe. Is the reaction spontaneous?
Consider the reaction between nitrogen and oxygen gas to form dinitrogen monoxide: 2 N2(g) + O2(g)  →  2 N2O(g), ΔHrxn = + 163.2 kJDetermine the sign of the entropy change for the system and the universe.
Some water is placed in a coffee-cup calorimeter. When 1.0 g of an ionic solid is added, the temperature of the solution increases from 21.5°C to 24.2°C as the solid dissolves. For the dissolving process, what are the signs for ΔSsys, ΔSsurr, and ΔSuniv?