ENTROPY AND FREE ENERGY Estimating a phase transition temperature from standard therm... DENNIS Using the thermodynamic information in the ALEKS Data tab, calculate the boiling point of bromine (Br,). Round your answer to the nearest degree. x10 X 5 nData X [+] Bond energies For example, the energy it takes to break an oxygen-hydrogen single bond, or carbon-carbon double bond. [-1 Thermodynamic properties of pure substances Standard thermodynamic quantities for selected substances at 25°C listed alphabetically by most important atom. AG (kJ/mol) So (J/mol-K) AHf (kJ/mol) substance Aluminum -485.0 Al3+ (aq) 28.3 0 Al (s) 0 50.9 -1582.3 Al203 (s) -1675.7 -1147.25 Al(OH)3 (s) Bromine -104.0 Br (aq) 152.2 0 Br2 (I) 245.5 3.1 30.9 Br2 (g) 198.7 -53.4 -36.3 HBr (g) Calcium -553.6 Ca2+ (aq) -795.4 CaCl2 (s) -634.9 CaO (s) Explanation se Privacy -985.2 Ca(OH)2 (s) ata [+] Bond energies For example, the energy it takes to break an oxygen-hydrogen single bond, or carbon-carbon d [-1 Thermodynamic properties of pure substances Standard thermodynamic quantities for selected substances at 25°C listed alphabetically by mos substance AHf (kJ/mol) AGf (kJ/mol) So (J/mol-K) Aluminum Al3+ (aq) -485.0 Al (s) 0 0 28.3 Al203 (s) Al(OH)3 (s) -1675.7 -1582.3 50.9 -1147.25 Bromine Br (aq) -104.0 Br2 (I) 0 10 152.2 Br2 (g) 30.9 245.5 3.1 HBr (g) 198.7 -36.3 -53.4 Calcium Ca2+ (aq) -553.6 CaCl2 (s) -795.4 CaO (s) -634.9 Ca(OH)2 (s) -985.2

Consider the following reaction: 5 H2(g) + 2 NO(g) → 2 NH3(g) + 2 H20(g) Based on the data in the table below, determine the standard Gibbs free energy of reaction, AG°, rxn in kJ. AH° (kJ mol-1) s° (JK-1 mol-1) H2(g) 130.7 NO(g) 92.1 210.8 NH3(g) -45.5 192.8 H20(g) -244.6 188.8

Use the table to calculate AG" for the following reactions at 25°C. rxn Species AG° f (kJ/mol) Mg(s) |02g) MgO(s) -569.6 SO2(g) -300.57 SO3(g) |-370.53 C2H2(g) 209.2 |CO2(g) -394.65 H20(1) -237.35 H20(g) -228.77 (a) 2 Mg(s) + O2g) → 2 MgO(s) kJ (b) 2 SO2(g) + O2g) → 2 SO3(g) kJ (c) 2 C2H2(g) + 5 02(g) → 4 CO2(g) + 2 H20(!) kJ

Gibbs free energy (G) is a measure of the spontaneity of a chemical reaction. It is the chemical potential for a reaction, and is minimized at equilibrium. It is defined as G=H-TS where H is enthalpy, T' is temperature, and S is entropy. The chemical reaction that causes aluminum to corrode in air is given by 4A1+30₂-2Al₂O₁ in which at 298 K, AH = -3352 kJ and AS = -625.1J/K Part A What is the standard Gibbs free energy for this reaction? Assume the commonly used standard reference temperature of 298 K Express your answer as an integer and include the appropriate units. ▸ View Available Hint(s) μA AG - 89 kJ Submit Previous Answers X Incorrect; Try Again; 4 attempts remaining Part B What is the Gibbs free energy for this reaction at 5975 K? Assume that AH and AS do not change with temperature. Express your answer to two decimal places and include the appropriate units. > View Available Hint(s) ? AG= Value Units Submit

Write the net ionic equation for this neutralization reaction, including the states of matter (-e., H*(aq)) for the reactants and products. 4. Given the following data: 2C,H,(g) + 70,(g) → 4CO,(g) + 6H,0(1) AH = -3120 kJ %3D 2H,0(1) → 2H,(g) + O,(g) AH = +572 kJ %3D (8)'O C,H,(g) + 2H,(g) → C,H,(g) AH = -312 kJ Find the AH of the following reaction: 4CO,(g) + 2H,O(1) → 2C,H,(g) + 50,(g)

17. For which of the following highly exothermic processes would you expect AH" and AG* to be about the same? (a) 2 Al(s) + 3/2 02(g) - Al;0:(s) (c) 2 Na(s) + 2 H20(1) → 2 N2OH(aq) + H2(g) (d) 2 NO(g) - N;O(g) (e) 2 Al(s) + Fe2O;(s) - 2 Fe(s) + Al;Oa(s) (b) 2 Ha(g) + Ozl8) - 2 H;0(g)

21. Given the following two equations CH5OH(1) + 3 O2(8) 2 СO2(g) + 3 Н20(1) AH = -1370 kJ С-Н(8) + 3 О2(s) → 2 CO2(g) + 2 H2O(1) AH = -1410 kJ Calculate AH for the reaction C2H4(8) + H2O(1) CH5OH(I) ΔΗ- a. -2780 kJ b. 2780 kJ с. 40 kJ d. 40 kJ

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Gaseous SO2Cl2 reacts with liquid water to form hydrogen chloride gas and liquid sulfuric acid. Using data tabulated in Appendix G of your text, calculate the enthalpy change, in units of kJ/mol, for the formation of 2 mol of liquid sulfuric acid. The answer is no -139.

K, for the reaction 9. Calculate the standard Gibbs free energy change, AG* (in kJ), at a temperature of 425 2 CO(g) + O₂(g) → 2 CO(g) O2(g) CO:(g) at 298 K: AH? (kJ/mol) Sº (J/mol K) AG (kJ/mol) A) -619.5 B) +82.9 C) -586.0 D) -534 E) -492.5 CO(g) -110.5 198 -137 0-393.5 214 205 0 -394