NOTE: For temperatures please always use Kelvin or Rankine. 1. Given the following data for NH,: Boiling Point -33.4°C; Melting point = -77.7°C; Cp(liq) 1.06cal/g-K; Cp(solid) = 0.502 cal/g-K; absolute entropy of gas at 25 deg C = 46.03 cal/gmol-K b. Calculate the absolute entropy of solid NH3 at its melting point at 1 atm pressure.

NOTE: For temperatures please always use Kelvin or Rankine. 1. Given the following data for NH,: Boiling Point -33.4°C; Melting point = -77.7°C; Cp(liq) 1.06cal/g-K; Cp(solid) = 0.502 cal/g-K; absolute entropy of gas at 25 deg C = 46.03 cal/gmol-K b. Calculate the absolute entropy of solid NH3 at its melting point at 1 atm pressure.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter16: Thermodynamics: Directionality Of Chemical Reactions

Section16.3: Measuring Dispersal Of Energy: Entropy

Problem 16.3CE

See similar textbooks

Similar questions

Use data from Appendix D to calculate the standardentropy change at 25°C for the reaction CH3COOH(g)+NH3(g)CH3NH2(g)+CO2(g)+H2(g) Suppose that 1.00 mol each of solid acetamide, CH3CONH2(s), and water, H2O(l), react to give thesame products. Will the standard entropy change belarger or smaller than that calculated for the reactionin part (a)?
For the process A(l) A(g), which direction is favored by changes in energy probability? Positional probability? Explain your answers. If you wanted to favor the process as written, would you raise or lower the temperature of the system? Explain.
What is the sign of the standard Gibbs free-energy change at low temperatures and at high temperatures for the formation of hydrogen sulfide from the elements? H2(g)+18S8(s)H2S(g)
Explain why absolute entropies can be measured.
Given that H f for HF(aq) is -320.1 kJ/mol and S for HF(aq) is 88.7 J/mol K, find Ka for HF at 25C.
A 220-ft3 sample of gas at standard temperature and pressure is compressed into a cylinder, where it exerts pressure of 2000 psi. Calculate the work (in J) performed when this gas expands isothermally against an opposing pressure of 1.0 atm. (The amount of work that can be done is equivalent to the destructive force of about 1/4 lb of dynamite, giving you an idea of how potentially destructive compressed gas cylinders can be if improperly handled!)
The standard molar entropy of iodine vapor, I2(g), is 260.7 J Kl mol-1 and the standard molar enthalpy of formation is 62.4 kJ/mol. a) Calculate the entropy change for vaporization of 1 mol of solid iodine (use data from Table 16.1 or Appendix J). b) Calculate the enthalpy change for sublimation of iodine. c) Assuming that rSdoes not change with temperature, estimate the temperature at which iodine would sublime (change directly from solid to gas).
Under what conditions is the entropy of a substance equal to zero?
What is the sign of the standard Gibbs free-energy change at low temperatures and at high temperatures for the explosive decomposition of TNT? Use your knowledge of TNT and the chemical equation, particularly the phases, to answer this question. (Thermodynamic data for TNT are not in Appendix G.) 2C7H5N3O6(s) 3N2(g) + 5H2O() + 7C(s) + 7CO(g)
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.
In the thermodynamic definition of a spontaneous process, why is it important that the phrase “continuous intervention” be used rather than just “intervention?”
Billions of pounds of acetic acid are made each year, much of it by the reaction of methanol with carbon monoxide. (AssumeT= 298 K.) CH3OH() + CO(g) CH3COOH() (a) By calculating the standard Gibbs free energy change, rG, for this reaction, show that it is product-favored. (b) Determine the standard Gibbs free energy change, rG,for the reaction of acetic acid with oxygen to form gaseous carbon dioxide and liquid water. (c) Based on this result, is acetic acid thermodynamicallystable compared with CO2(g) and H2O()? (d) Is acetic acid kinetically stable compared with CO2(g)and H2O()?