Consider the reaction: 2SO2(g) + O2(g) → 2SO3 (9) Using standard absolute entropies at 298 K, calculate the entropy change for the system when 1.63 moles of SO2 (g) react at standard conditions. J Substance So K mol SO3 (9) 256.8 SO2(g) 248.2 02 (9) 205.1 J/K ASO system Submit Answer Retry Entire Group 9 more group attempts remaining

The standard molar entropy of methanol vapor, CH3OH(g), is 239.8 J K1 mol-1. (a) Calculate the entropy change for the vaporization of 1 mol methanol (use data from Table 16.1 or Appendix J). (b) Calculate the enthalpy of vaporization of methanol, assuming that rS doesnt depend on temperature and taking the boiling point of methanol to be 64.6C.

Explain why absolute entropies can be measured.

A key component in many chemical engineering designs is the separation of mixtures of chemicals. (a) What happens to the entropy of the system when a chemical mixture is separated? (b) Are designs for chemical separation more likely to rely on spontaneous or nonspontaneous processes?

It has been demonstrated that buckminsterfullerene (C60), another allotrope of carbon (Section 2.3), may be converted into diamond at room temperature and 20,000 atmospheres pressure (about 2 GPa). The standard enthalpy of formation, fH, for buckminsterfullerene is 2320 kJ/mol at 298.2 K. a. Calculate rH for the conversion of C60 to diamond at standard state conditions and 2982 K. b. Assuming that the standard entropy per mole of carbon in both C60 and diamond is comparable (both about 23 J/K mol), is the conversion of C60 to diamond product-favoredat room temperature?

According to Lambert, leaves lying in the yard and playing cards that are in disarray on a table have not undergone an increase in their thermodynamic entropy. Suggest another reason why leaves and playing cards may not be a good analogy for the entropy of a system containing, for example, only H2O molecules or only O2 molecules.

Chemists and engineers who design nuclear power plants have to worry about high-temperature reactions because it is possible for water to decompose. (a) Under what conditions does this reaction occur spontaneously? 2H2O(g) 2H2(g) + O2(g) (b) Under conditions where the decomposition of water is spontaneous, do nuclear engineers have to worry about an oxygen/hydrogen explosion? Justify your answer.

What is the sign of the standard Gibbs free-energy change at low temperatures and at high temperatures for the synthesis of ammonia? 3H2(g) + N2(g) 2NH3(g)

The evaporation of one mole of water at 298 K has a standard free allergy change of 8.58 kJ. H2O(l)H2O(g)G298=8.58kJ (a) Is the evaporation of water under standard thermodynamic conditions spontaneous?. (b) Determine the equilibrium constant, KP, for this physical process. (c) By calculating G, determine if the evaporation of water at 298 K is spontaneous when the partial pressure of water, PH2O, is 0.011 atm.. (d) If the evaporation of water were always nonspontaneous at room temperature, wet laundry would never dry when placed outside. In order for laundry to dry, what must be the value of PH2O in the air?

When ammonium chloride is added to water and stirred, it dissolves spontaneously and the resulting solution feels cold. Without doing any calculations, deduce the signs of G, H, and S for this process, and justify your choices.