Which of these processes is spontaneous? a. the combustion of natural gas b. the extraction of iron metal from iron ore c. a hot drink cooling to room temperature d. drawing heat energy from the ocean's surface to power a ship

Which of these processes are nonspontaneous? Are the nonspontaneous processes impossible? a. a bike going up a hill b. a meteor falling to Earth c. obtaining hydrogen gas from liquid water d. a ball rolling down a hill

Two systems, each composed of two particles represented by circles, have 20 J of total energy. Which system, A or B, has the greater entropy? Why?

Two systems, each composed of three particles represented by circles, have 30 J of total energy. How many energetically equivalent ways can you distribute the particles in each system? Which system has greater entropy?

Calculate the change in entropy that occurs in the system when 1.50 mol of isopropyl alcohol (C₃H₈O) melts at its melting point (-89.5 °C). See Table 12.9 for heats of fusion.

Calculate the change in entropy that occurs in the system when 1.50 mol of diethyl ether (C₄H₁₀O) condenses from a gas to a liquid at its normal boiling point (34.6 °C). See Table 12.7 for heats of vaporization.

Without doing any calculations, determine the sign of ΔS_sys for each chemical reaction. a. 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g) c. Na(s) + 2 Cl₂(g) → NaCl(s) d. N₂(g) + 3 H₂(g) → 2 NH₃(g)

Without doing any calculations, determine the sign of ΔS_sys for each chemical reaction. b. CH₂=CH₂( g) + H₂( g) → CH₃CH₃( g)

Without doing any calculations, determine the signs of ΔS_sys and ΔS surr for each chemical reaction. In addition, predict under what temperatures (all temperatures, low temperatures, or high temperatures), if any, the reaction is spontaneous. a. C₃H₈(g) + 5 O₂(g) → 3 CO₂(g) + 4 H₂O(g) ΔH°_rxn = -2044 kJ

Without doing any calculations, determine the signs of ΔS_sys and ΔS_surr for each chemical reaction. In addition, predict under what temperatures (all temperatures, low temperatures, or high temperatures), if any, the reaction is spontaneous. c. C₃H₈(g) + 5 O₂(g) → 3 CO₂(g) + 4 H₂O(g) ΔH°_rxn = -2044 kJ

Calculate ΔS_surr at the indicated temperature for each reaction. d. ΔH°_rxn = +114 kJ; 77 K

Given the values of ΔH°_rxn, ΔS°_rxn, and T, determine ΔS_univ and predict whether or not each reaction is spontaneous. (Assume that all reactants and products are in their standard states.) a. ΔH°_rxn = +135 kJ; ΔS°_rxn = -282 J/K; T = 298 K

Given the values of ΔH°_rxn, ΔS°_rxn, and T, determine ΔS_univ and predict whether or not each reaction is spontaneous. (Assume that all reactants and products are in their standard states.) c. ΔH°_rxn = -135 kJ; ΔS°_rxn = -282 J>K; T = 298 K

Given the values of ΔH°_rxn, ΔS°_rxn, and T, determine ΔS_univ and predict whether or not each reaction is spontaneous. (Assume that all reactants and products are in their standard states.) a. ΔH°_rxn = -75 kJ; ΔS°_rxn = -127 J/K; T = 298 K

Given the values of ΔH°_rxn, ΔS°_rxn, and T, determine ΔS_univ and predict whether or not each reaction is spontaneous. (Assume that all reactants and products are in their standard states.) c. ΔH°_rxn = +75 kJ; ΔS°_rxn = -127 J/K; T = 298 K

Calculate the change in Gibbs free energy for each of the sets of ΔH°_rxn, ΔS°_rxn, and T given in Problem 44. Predict whether or not each reaction is spontaneous at the temperature indicated. (Assume that all reactants and products are in their standard states.)

Calculate the free energy change for this reaction at 25 °C. Is the reaction spontaneous? (Assume that all reactants and products are in their standard states.) 2 Ca(s) + O₂( g) → 2 CaO(s) ΔH°_rxn = -1269.8 kJ; ΔS°_rxn = -364.6 J/K

Fill in the blanks in the table. Both ΔH and ΔS refer to the system.

Predict the conditions (high temperature, low temperature, all temperatures, or no temperatures) under which each reaction is spontaneous. a. H₂O(g) → H₂O(l) b. CO₂(s) → CO₂(g) c. H₂(g) → 2 H(g) d. 2 NO₂(g) → 2 NO(g) + O₂(g) (endothermic)

How does the molar entropy of a substance change with increasing temperature?

For each pair of substances, choose the one that you expect to have the higher standard molar entropy (S°) at 25 °C. Explain your choices. a. CO(g); CO₂(g) b. CH₃OH(l); CH₃OH(g) c. Ar(g); CO₂(g) d. CH₄(g); SiH₄(g) e. NO₂(g); CH₃CH₂CH₃(g) f. NaBr(s); NaBr(aq)

Rank each set of substances in order of increasing standard molar entropy (S°). Explain your reasoning. a. NH₃(g); Ne(g); SO₂(g); CH₃CH₂OH(g); He(g) c. CH₄(g); CF₄(g); CCl₄(g)

Rank each set of substances in order of increasing standard molar entropy (S°). Explain your reasoning. b. H₂O(s); H₂O(l); H₂O(g)

Rank each set of substances in order of increasing standard molar entropy (S°). Explain your reasoning. a. I₂(g); F₂(g); Br₂(g); Cl₂(g) b. H₂O(g); H₂O₂(g); H₂S(g) c. C(s, graphite); C(s, diamond); C(s, amorphous)

Use data from Appendix IIB to calculate ΔS°_rxn for each of the reactions. In each case, try to rationalize the sign of ΔS°_rxn . b. C(s) + H₂O(g) → CO(g) + H₂(g)

Use data from Appendix IIB to calculate ΔS°_rxn for each of the reactions. In each case, try to rationalize the sign of ΔS°_rxn. c. CO(g) + H₂O(g) → H₂(g) + CO₂(g)

Use data from Appendix IIB to calculate ΔS°_rxn for each of the reactions. In each case, try to rationalize the sign of ΔS°_rxn. d. 2 H₂S(g) + 3 O₂(g) → 2 H₂O(l) + 2 SO₂(g)