Thermodynamics

 1) If the equilibrium constant for the following reaction is 0.15 at 1227°C, which of the following statements are true?

2SO₂(g) + O₂(g) 2SO₃(g)

     (a) The reaction is product-favored.

     (b) The reaction is reactant-favored.

     (c) ΔG° < 0.

     (d) ΔG° > 0.

     (e) ΔG° = 0.

 2) Which of the following statements is false?

     (a) The entropy of an element in its standard state at room temperature is zero.

     (b) Gibbs free energy is energy that is available to do work.

     (c) Entropy measures dispersal or disorder of a sample of matter.

 3) Which of the following best illustrates the conservation of Gibbs free energy?

     (a) Using a gallon of gasoline to power a bus to transport twenty people five miles.

     (b) Using a gallon of gasoline to power a sports utility vehicle to transport one person 15 miles.

     (c) Using a gallon of gasoline to power a small car to transport two people 30 miles.

     (d) Using a gallon of gasoline on a bonfire.

 4) If the equilibrium constant for the following reaction is 1.845 at 183°C, which of the following statements are true?

CO(g) + H₂O(g) CO₂(g) + H₂(g)

     (a) The reaction is product-favored.

     (b) The reaction is reactant-favored.

     (c) ΔG° < 0.

     (d) ΔG° > 0.

     (e) ΔG° = 0.

 5) Which of the following statements is false?

     (a) Entropies of gases are usually much larger than entropies of liquids.

     (b) A reaction is sure to be product-favored if it is endothermic and the atoms of the reaction system are more ordered at the end of the reaction.

     (c) At lower temperatures enthalpy change has a more significant effect on whether a reaction will be product-favored than it does at higher temperatures.

 6) Which of the following is the worst example of conservation of Gibbs free energy?

     (a) Destroying aluminum cans by dissolving them in acid.

     (b) Obtaining aluminum to make new soda cans by melting recycled cans.

     (c) Riding the bus to campus.

     (d) Washing and reusing milk bottles collected at a recycling station.

 7) Which of the following statements is false?

     (a) For the same mass of the same substance, entropy values are very similar at all temperatures.

     (b) At higher temperatures entropy change has a more significant effect on whether a process is product-favored than it does at lower temperatures.

     (c) A product-favored reaction has a negative value for Gibbs free energy change of the system.

 8) Which of the following best illustrates conservation of Gibbs free energy?

     (a) Burning coal to produce electricity used to light an empty room.

     (b) Burning coal to produce electricity used to charge the battery in your car.

     (c) Burning coal to produce electricity to power a stereo while you're asleep.

     (d) Burning coal to produce electricity to grill a steak outdoors on an electric grill.

 9) Which of the following statements is false?

     (a) When a solid dissolves in a liquid solvent the entropy usually increases.

     (b) The second law of thermodynamics states that the total entropy of the universe is continually decreasing.

     (c) At lower temperatures, enthalpy change has a more significant effect on whether a reaction is product-favored that is does at higher temperatures.

10) Which of the following statements is false?

     (a) Ionic solids with weaker attractions have higher entropies than ionic solids with stronger attractions.

     (b) At the same temperature, the entropy of a complex molecule is usually larger than the entropy of a simple molecule.

     (c) It is more probable that energy will concentrate in a confined region rather than disperse.