Top of Form1. For the following reaction at 25.0 C,

2 C(s) + O2(g) 2 CO(g)

calculate given = 179.1 J/K and = -221.1 kJ.(Points : 10)

-9023 J/K -562.3 J/K -167.7 J/K +170.2 J/K +920.7 J/K

2. The following processes occur spontaneously at 25 C. Which of these processes are endothermic?1.the combustion of methane to produce water and carbon dioxide

2.the expansion of an ideal gas into a vacuum

3.the melting of ice

(Points : 10)

1 only 2 only 3 only 1 and 2 2 and 3

3. A statement of the second law of thermodynamics is that(Points : 10)

spontaneous reactions are always exothermic. energy is conserved in a chemical reaction. the Gibbs free energy is a function of both enthalpy and entropy. S = - H for any chemical reaction. in a spontaneous process, the entropy of the universe increases.

4. Which reaction is likely to have a negative change in entropy?(Points : 10)

2 NH3(g) N2(g) + 3 H2(g) CaCO3(s) CaO(s) + CO2(g) NaCl(s) Na+(aq) + Cl-(aq) N2O4(g) 2 NO2(g) 2 CO(g) 2 C(s) + O2(g)

5. At what temperatures will a reaction be spontaneous if H = -76.0 kJ and S = +231 J/K?(Points : 10)

All temperatures below 329 K Temperatures between 0 K and 231 K All temperatures above 329 K The reaction will be spontaneous at any temperature. The reaction will never be spontaneous.

6. Diluting concentrated sulfuric acid with water can be dangerous. The temperature of the solution can increase rapidly. What are the signs of H, S, and G for this process?(Points : 10)

H < 0, S > 0, G < 0 H < 0, S < 0, G < 0 H < 0, S > 0, G > 0 H > 0, S > 0, G < 0 H > 0, S < 0, G > 0

7. All of the following processes lead to a decrease in entropy EXCEPT(Points : 10)

decreasing the temperature of a gas. melting a solid chemical reactions that decrease the number of moles of gas. forming pure substances from mixtures. condensing a liquid

8. At what temperatures will a reaction be spontaneous if H = +158 kJ and S = +411 J/K?(Points : 10)

All temperatures below 384 K Temperatures between 158 K and 411 K All temperatures above 384 K The reaction will be spontaneous at any temperature. The reaction will never be spontaneous.

9. Reactants A and B are placed in an empty flask. If the reaction A(g) + B(g) f 2 C(g) has Kp > 1, which of the following statements are correct?1.The forward reaction is spontaneous.

2.The forward rate of reaction is fast.

3.The reaction is reactant-favored.

(Points : 10)

1 only 2 only 3 only 1 and 2 1, 2, and 3

10. Which of the following processes involves an increase in entropy?(Points : 10)

the combination of H2(g) and N2(g) gas to form NH3(g) the combination of Na and Cl to form NaCl in water the evaporation of liquid water to steam the condensation of ethanol the crystallization of a solid (i.e., CO2(s))

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