- Ch.1 - Matter, Measurement & Problem Solving106
- Ch.2 - Atoms & Elements97
- Ch.3 - Molecules, Compounds & Chemical Equations134
- Ch.4 - Chemical Quantities & Aqueous Reactions115
- Ch.5 - Gases98
- Ch.6 - Thermochemistry84
- Ch.7 - Quantum-Mechanical Model of the Atom49
- Ch.8 - Periodic Properties of the Elements81
- Ch.9 - Chemical Bonding I: The Lewis Model79
- Ch.10 - Chemical Bonding II: Molecular Shapes & Valence Bond Theory78
- Ch.11 - Liquids, Solids & Intermolecular Forces41
- Ch.12 - Solids and Modern Material35
- Ch.13 - Solutions66
- Ch.14 - Chemical Kinetics83
- Ch.15 - Chemical Equilibrium52
- Ch.16 - Acids and Bases107
- Ch.17 - Aqueous Ionic Equilibrium130
- Ch.18 - Free Energy and Thermodynamics74
- Ch.19 - Electrochemistry87
- Ch.20 - Radioactivity and Nuclear Chemistry50
- Ch.21 - Organic Chemistry143
Chapter 18, Problem 49
How does the molar entropy of a substance change with increasing temperature?
Video transcript
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. d. 2 NO2(g) → 2 NO(g) + O2(g) (endothermic)
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. e. NO2( g); CH3CH2CH3( g)
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)
Rank each set of substances in order of increasing standard molar entropy (S°). Explain your reasoning. b. H2O(s); H2O(l ); H2O( g)