Chemistry Chemistry Practice Problems Solutions Library

Entropy Solutions Library

Access 295 Entropy video and text solutions to help you complete your homework. Need to revisit the concept? Watch our Entropy learn videos.

Browse Solutions

295 solutions

Entropy

Q. Consider these three changes in the possible distributions of six gaseous particles within three interconnected boxes. Which change has a positive ΔS?

Solved • Jan 3, 2019

Entropy

Q. Given the thermodynamic data below, calculate ΔS and ΔS surr for the following reaction at 25°C and 1 atm:                       XeF  6(g) →XeF4(s)...

Solved • Dec 3, 2018

Entropy

Q. For rubidium ΔH°vap = 69.0 kJ/mol at 686°C, its boiling point. Calculate ΔS°, and q for the vaporization of 1.00 mole of rubidium at 686°C and 1.00...

Solved • Dec 3, 2018

Entropy

Q. Rank the contents of the following containers in order of decreasing entropy.

Solved • Dec 3, 2018

Entropy

Q. Predict the sign of ΔS° and then calculate ΔS° for each of the following reactions.b. 2SO3 (g) → 2SO2 (g) + O2 (g)

Solved • Nov 30, 2018

Entropy

Q. For each of the following pairs, which substance has the greater value of S?b. N2O(g) (at 1 atm, 25°C) or He(g) (at 1 atm, 25°C)

Solved • Nov 30, 2018

Entropy

Q. The enthalpy of vaporization of ethanol is 38.7 kJ/mol at its boiling point (78°C). Determine ΔSsys, ΔSsurr, and ΔSuniv when 1.00 mole of ethanol i...

Solved • Nov 30, 2018

Entropy

Q. Ethanethiol (C2H5SH; also called ethyl mercaptan) is commonly added to natural gas to provide the “rotten egg” smell of a gas leak. The boiling poi...

Solved • Nov 30, 2018

Entropy

Q. Calculate ΔSsurr for the following reactions at 25°C and 1 atm.a. C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(l)     ΔH° = -2221 kJ

Solved • Nov 30, 2018

Entropy

Q. Use the standard entropy data in Appendix G to determine the change in entropy for each of the reactions listed below. All the processes occur at t...

Solved • Nov 29, 2018

Entropy

Q. By calculating ΔSuniv at each temperature, determine if the melting of 1 mole of NaCl(s) is spontaneous at 500 °C and at 700 °C.What assumptions ar...

Solved • Nov 29, 2018

Entropy

Q. Using the relevant S°298 values listed in Appendix G, calculate ΔS°298 for the following change:(a) N2(g) + 3H2(g) ⟶ 2NH3(g)

Solved • Nov 29, 2018

Entropy

Q. Determine the entropy change for the combustion of gaseous propane, C 3H8, under the standard conditions to give gaseous carbon dioxide and water.

Solved • Nov 29, 2018

Entropy

Q. Calculate ΔS°298 for the following change.(a) SnCl4(l) ⟶ SnCl4(g)

Solved • Nov 29, 2018

Entropy

Q. The boiling point of chloroform, CHCl 3, is 61.2°C. Use Trouton’s rule to estimate the enthalpy of vaporization of chloroform.

Solved • Nov 28, 2018

Entropy

Q. Iron melts at 1535°C and its enthalpy of fusion is 13.8 kJ/mol. Calculate the entropy of fusion per mole of iron.

Solved • Nov 28, 2018

Entropy

Q. When heated, the DNA double helix separates into two random coil single strands. When cooled, the random coils reform the double helix: double heli...

Solved • Nov 28, 2018

Entropy

Q. Consider the following reaction:   2NOBr(g) ⥫⥬ 2NO(g) + Br 2(g)      K = 0.42 at 373 KGiven that S° of NOBr(g) = 272.6 J/mol·K and that ΔS°rxn and ...

Solved • Nov 28, 2018

Entropy

Q. Write the balanced chemical equation for the combustion of methane, CH4(g), to give carbon dioxide and water vapor. Explain why it is difficult to ...

Solved • Nov 26, 2018

Entropy

Q. Consider two processes: sublimation of I2 (s) and melting of I2 (s) (Note: the latter process can occur at the same temperature but somewhat higher...

Solved • Nov 26, 2018

Entropy

Q. At room temperature, the entropy of the halogens increases from I2 to Br2 to Cl2. Explain.

Solved • Nov 26, 2018

Entropy

Q. Arrange the following set of systems in order of increasing entropy. Assume one mole of each substance and the same temperature for each member of ...

Solved • Nov 26, 2018

Entropy

Q. Calculate ΔSuniv for the formation of CH3OH(l) from its elements, and state whether the reaction is spontaneous at 298 K.

Solved • Nov 21, 2018

Entropy

Q. Find ΔS°rxn for the formation of CH3OH(l) from its elements.

Solved • Nov 21, 2018

Entropy

Q. Find ΔS°rxn for the formation of HI(g) from its elements.

Solved • Nov 21, 2018

Entropy

Q. Calculate ΔSuniv for the formation of Cu2O(s) from its elements, and state whether the reaction is spontaneous at 298 K.

Solved • Nov 21, 2018

Entropy

Q. Find ΔS°rxn for the formation of Cu2O(s) from its elements.

Solved • Nov 21, 2018

Entropy

Q. Find ΔS°rxn for the combustion of ammonia to nitrogen dioxide and water vapor. Is the sign of ΔS°rxn as expected?

Solved • Nov 21, 2018

Entropy

Q. Find ΔS°rxn for the combustion of ethane (C2H6) to carbon dioxide and gaseous water. Is the sign of ΔS°rxn as expected?

Solved • Nov 21, 2018

Entropy

Q. For the following reaction, predict the sign and find the value of ΔS°rxn:(a) 3NO2(g) + H2O(l) ⟶ 2HNO3(l) + NO(g)

Solved • Nov 21, 2018

Entropy

Q. Without consulting Appendix B, arrange the group in order of increasing standard molar entropy (S°). Explain.(c) SF6(g), SF4(g), S2F10(g)

Solved • Nov 21, 2018

Entropy

Q. Predict which substance has greater molar entropy. Explain.(a) P4(g) or P2(g)(b) HNO3(aq) or HNO3(l)(c) CuSO4(s) or CuSO4·5H2O(s)

Solved • Nov 21, 2018

Entropy

Q. Predict which substance has greater molar entropy. Explain.(a) CH3OH(l) or C2H5OH(l)(b) KClO3(s) or KClO3(aq)(c) Na(s) or K(s)

Solved • Nov 21, 2018

Entropy

Q. Predict which substance has greater molar entropy. Explain.(a) NO2(g) or N2O4(g)(b) CH3OCH3(l) or CH3CH2OH(l)(c) HCl(g) or HBr(g)

Solved • Nov 21, 2018

Entropy

Q. Predict the sign of ΔS for the process: C 2H5OH(g) (350 K and 500 torr) ⟶ C2H5OH(g) (350 K and 250 torr)

Solved • Nov 21, 2018

Entropy

Q. Predict the sign of ΔSsys for the following process:(c) An apple tree bears fruit.

Solved • Nov 21, 2018

Entropy

Q. Nitric oxides, NO and NO2, contribute to air pollution, acid rain, and the depletion of the ozone layer. After NO forms in the combustion chamber o...

Solved • Sep 19, 2018

Entropy

Q. Using the following data, calculate ΔSfus and ΔSvap for Cs. 

Solved • Sep 11, 2018

Entropy

Q. Entropy of Reaction for Nitrogen Dioxide Formation Nitric oxides. NO and NO2, contribute to air pollution, acid rain, and the depletion of the ozon...

Solved • Sep 3, 2018

Entropy

Q. Part BCalculate the standard entropy change for the reaction P4 (g) + 5O2 (g) → P4O10 (s) using the data from the following table: Express your ans...

Solved • Sep 3, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25°C. S° values can be found here. Mg(OH)2 (s) + 2HCl (g) → MgCl2 (s) + 2H2O (g) 

Solved • Aug 29, 2018

Entropy

Q. The ΔHvap of a certain compound is 28.26 kJ mol and its ΔSvap is 50.01 J•mol-1•K-1. What is the boiling point of this compound?

Solved • Aug 28, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction, 2SO2 (g) + O2 (g) → 2SO3 (g) given S° [SO2 (g)] = 248.2 J/K • mol. S° [O2 (g)] = ...

Solved • Aug 27, 2018

Entropy

Q. A reaction had ΔH°rxn = - 130 kJ and ΔS°rxn = 316 J/K. Part AAt what temperature is the change in entropy for the reaction equal to the change in e...

Solved • Aug 22, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25 °C. S° values can be found here. HCl (g) + NaOH (s) → NaCl (s) + H2O (l) 

Solved • Aug 8, 2018

Entropy

Q. Use the data from this table of thermodynamic properties to calculate the values of delta S°rxn for each of the following reactions at 25 °C. (a) 4...

Solved • Aug 8, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25 °C. S° values can be found here.C3H8 (g) + 5O2 (g) → 3CO2 (g) + 4H2O (g)

Solved • Aug 7, 2018

Entropy

Q. Identify the process in which the entropy increases.a. the phase transition from a solid to a gasb. the phase transition from a gas to a solidc. th...

Solved • Jul 30, 2018

Entropy

Q. Sodium reacts violently with water according to the equation: 2 Na(s) + 2 H2O(l) →2NaOH(aq) + H2(g) The resulting solution has a higher temperature...

Solved • Jul 30, 2018

Entropy

Q. Place the following in order of increasing standard molar entropy.H2O(l) H2O(g) H2O(s) a. H2O(g), H2O(s), H2O(l) b. H2O(l), H2O(s), H2O(g) c. H2O(g...

Solved • Jul 30, 2018

Entropy

Q. Entropy is a measure of a. free energy. b. the heat of a reaction. c. the rate of a reaction. d. molecular randomness. 

Solved • Jul 30, 2018

Entropy

Q. Which provides the greatest decrease in entropy?

Solved • Jul 30, 2018

Entropy

Q. The entropy of 1 mole of N2 (g) is greater than the entropy of 1 mole of N2(aq).a. Trueb. False 

Solved • Jul 24, 2018

Entropy

Q. The entropy of 0.002 mole of CH2CI2 (aq) is greater than the entropy of 0.002 mole of CH2CI2 (l).a. Trueb. False

Solved • Jul 24, 2018

Entropy

Q. The entropy of 0.5 mole LiBr (s) at 290 K is greater than the entropy of 0.5 mole LiBr (s) at 330Ka. Trueb. False 

Solved • Jul 24, 2018

Entropy

Q. The temperature of a 874 g piece of granite is increased from 19.2°C to 69.2°C. What is its change in entropy J/K)? The specific heat capacity of g...

Solved • Jul 3, 2018

Entropy

Q. A 15 g piece of metal (138.4 g/mol) melts at 1774 °C and its enthalpy of fusion is 17.4/mol. Calculate the entropy of fusion (J/K) of the metal. En...

Solved • Jul 3, 2018

Entropy

Q. Consider the reaction: I2 (g) + Cl2 (g) → 2ICl (g) Using standard absolute entropies at 298K, calculate the entropy change for the system when 2.49...

Solved • Jul 3, 2018

Entropy

Q. Use the data from this table of thermodynamic properties to calculate the values of ΔS°rxn for each of the following reactions at 25° C. 2CO(g) + O...

Solved • Jun 26, 2018

Entropy

Q. Calculate ΔS° compositefunction (in J/mol • K) for the following reaction. 2HCl (g) + Pb (s) → PbCl2 (s) + H2 (g)

Solved • Jun 25, 2018

Entropy

Q. Which of the following processes shows a decrease in entropy of the system? NaClO3 (s) → Na+ (aq) ClO3- (aq) CH3OH (l) → CO (g) + 2H 2 (g) H2O(l) →...

Solved • Jun 4, 2018

Entropy

Q. Given the hypothetical reaction. 4 X(s) + 6Y(s) → 4Z (s) + 9A(g) Calculate Δ S for this reaction at 25°C, given the following absolute entropies: S...

Solved • May 30, 2018

Entropy

Q. Suppose a heat source generates heat at a rate of 54.0 W (1 W = 1 J/s). How much entropy does this produce per hour in the surroundings at 25.0 °C?...

Solved • May 30, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25°C. S° values can be found here.HCl(g)+ NaOH(s) → NaCl(s) + H2O(l)

Solved • May 30, 2018

Entropy

Q. The ΔHvap of a certain compound is 48.17 kJ mol-1 and its ΔSvap is 52.91 J mol-1•K-1. What is the boiling point of this compound?

Solved • May 30, 2018

Entropy

Q. Using the following data, calculate ΔSfus (J•K -1•mol -1) and  ΔSvap (J•K -1•mol -1) for Na.

Solved • May 27, 2018

Entropy

Q. The normal boiling point of ethanol (C2H5OH) is 78.3 ° C and its molar enthalpy of vaporization it 38.56 kJ/mol. What is the change in entropy of t...

Solved • May 20, 2018

Entropy

Q. Select the molecule with the highest gas-phase absolute entropy at 25 ºC. a) CH4 b) C4H10 c) C3H8 d) C2H6

Solved • May 3, 2018

Entropy

Q. Which of the following would have the highest entropy assuming one mole of each substance and the same temperature for each. a) HBr(g) b) H2(g) c) ...

Solved • May 3, 2018

Entropy

Q. Consider the following reaction at 298 ºK: C(graphite) + 2Cl2(g)→CCl4(l) Δ H = -139 kJ Calculate the following quantities. Find standard entropy va...

Solved • Apr 29, 2018

Entropy

Q. Given the values of ΔHºrxn, ΔSºrxn, and T below determine ΔSuniv.ΔHºrxn = -81 kJ,ΔSrxn = -149 J/K,T = 301 ºKExpress your answer using two significa...

Solved • Apr 18, 2018

Entropy

Q. For one mole of substance at a given temperature, select the member in each pair with the higher entropy.a. P2(g), P4(g)b. CaF2(s), BaCl2(s)c. CuSO...

Solved • Mar 30, 2018

Entropy

Q. Consider the reaction:3 Fe2O3(s) + H2(g) → 2 Fe3O4(s) + H2O(g)Using standard absolute entropies at 298K, calculate the entropy change for the syste...

Solved • Mar 30, 2018

Entropy

Q. Using the data in the table, calculate the standard entropy changes (J/mol•K) for the following reactions at 25 °C.S(s) + O2(g) → SO2(g)MgCO3(s) → ...

Solved • Mar 30, 2018

Entropy

Q. The ΔHvapo of a certain compound is 13.08 kJ mol-1 and its ΔSvapo is 67.74 J mol-1 K-1.What is the normal boiling point of this compound?

Solved • Mar 30, 2018

Entropy

Q. ΔS is positive for the reaction _________________.a. 2NO(g) + O 2(g) → 2NO2(g)b. 2N2(g) + 2H2(g) → 2NH3(g)c. C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) d...

Solved • Mar 28, 2018

Entropy

Q. Using the following data, calculate ΔSfus and ΔSvap for HBr.Determine the entropy change when 4.80 mol of HBr (f) freezes at atmospheric pressure. 

Solved • Mar 28, 2018

Entropy

Q. CO(NH2)2(aq) + H2O(l) → CO2(g) +2NH3(g) ΔS° = +354.8 J/mol*KGiven the data below, calculate the ΔS° f for UreaSubstance S° (J/molK)H2O (l) 69.96CO2...

Solved • Mar 23, 2018

Entropy

Q. For a given compound, list the decreasing order of entropy for a solid, liquid, and gas.a. solid > gas > liquidb. liquid > solid > gasc...

Solved • Mar 22, 2018

Entropy

Q. Which of the following is true for an endothermic process?a. qsys > 0, ΔSsurr < 0b. qsys < 0, ΔSsurr > 0c. qsys < 0, ΔSsurr < 0d....

Solved • Mar 22, 2018

Entropy

Q. The enthalpy of vaporization of methanol is 35.27 kJ mol-1 at its boiling point of 64.1°Ca. Calculate the entropy of vaporization of methanol at th...

Solved • Mar 21, 2018

Entropy

Q. The heat of vaporization of methanol, CH3OH, is 35.2 kJ/mol. Its boiling point is 64.6°C. What is the change in entropy for the vaporization of met...

Solved • Mar 21, 2018

Entropy

Q. Calculate ΔS°rxn for the following reaction:4Cr(s) + 3O2(g) → 2Cr2O3(s).Substance            ΔS°, J/K·molCr(s)                        23.77O2(g)   ...

Solved • Mar 20, 2018

Entropy

Q. Given the values of ΔH∘rxn, ΔS∘rxn, and T below, determine ΔSuniv.a) ΔH∘rxn = 87 kJ , ΔS∘rxn = 146 J/K , T= 296 K, will this be spontaneous or not ...

Solved • Mar 20, 2018

Entropy

Q. Arrange these gases in order of decreasing standard molar entropy:Rank from largest to smallest.Cl2SO3Kr

Solved • Mar 19, 2018

Entropy

Q. Given the values of ΔH∘rxn, ΔS∘rxn, and T below, determine ΔSuniv.a. ΔH∘rxn = 84 kJ , ΔS∘rxn = 144 J/K , T = 303 Kb. ΔH∘rxn = 84 kJ , ΔS∘rxn = 144 ...

Solved • Mar 7, 2018

Entropy

Q. Which of the following processes have a ΔS > 0?a. 2NH3(g) + CO2(g) → NH2CONH2(aq) + H2O(l)b. lithium fluoride forms from its elementsc. 2HF(g) →...

Solved • Mar 6, 2018

Entropy

Q. Calculate ΔSfus and ΔSvap for Na.

Solved • Mar 2, 2018

Entropy

Q. Predict the sign of the entropy change, ΔS°, for each of the reaction displayed.i) 2NO2 (g) → N2 (g) + 2O2 (g)ii) C5H12 (g) + 8O2 (g) → 5CO2 (g) + ...

Solved • Feb 22, 2018

Entropy

Q. Predict the sign of the entropy change, ΔS°, for the following reaction.Pb2+ (aq) + 2Cl− (aq) → PbCl2(s)a) Negativeb) Positive                     ...

Solved • Feb 22, 2018

Entropy

Q. Predict the sign of the entropy change, ΔS°, for each of the reaction displayed. Drag the appropriate items to their respective bins.

Solved • Feb 22, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25°C.2CH3OH(g) + 3O2(g) → 2CO2(g) + 4H2O(g)

Solved • Feb 20, 2018

Entropy

Q. The ΔH°vap for pure water is 40.65 kJ/mol. Calculate the ΔS°vap for pure water.

Solved • Feb 19, 2018

Entropy

Q. Calculate the standard entropy change for the following reaction at 25°C.MgCl2(s) + H2O(l) → MgO(s )+ 2HCl(g) 

Solved • Feb 19, 2018

Entropy

Q. Predict how the entropy of the substance is affected in the following processes. CH4(g, 125°c) → CH4(g, 200°C)  a) increases b) decreases c) re...

Solved • Feb 16, 2018

Entropy

Q. Predict how the entropy of the substance is affected in the following process? Br2 (l, 1 bar, 25°celcius) yields Br2 (g, 1 bar, 25°Celsius) a) In...

Solved • Feb 15, 2018

Entropy

Q. Calculate ΔS°rxn for this balanced chemical equation.2NO(g) + O2(g) → 2NO2(g)Express your answer to one decimal place and include the appropriate u...

Solved • Feb 15, 2018

Entropy

Q. Predict how the entropy of the substance is affected in the following process:                                           Ar(l) → Ar(g) a) increases...

Solved • Feb 15, 2018

Entropy

Q. Predict how the entropy of the substance is affected in the following processes:

Solved • Feb 15, 2018

Entropy

Q. Nitric oxides, NO and NO2, contribute to air pollution, acid rain, and the depletion of the ozone layer. After NO forms in the combustion chamber o...

Solved • Feb 15, 2018