As always… OWL Lon-Capa assignments Lecture videos Textbook HW due Monday Quiz #4 opens Monday Lecture videos Textbook Read Do text homework

Exam II Thursday, November 1, 7:00-9:00 pm; rooms are on the website. Conflict: (11/1) 4:30-6:30pm in 219 Greg; sign up in 1026 CA starting Friday Conflict with conflict? Email me right away. Review sessions: Monday (10/29): 217 Noyes Lab (6-8 pm) Tuesday (10/30): 163 Noyes Lab (6-8:30 pm)

Exam II Practice exam will be posted sometime today. Take when you feel ready for the exam. Take as an actual exam (not just more practice problems). See the front of the exam for information that you are given and the number of problems.

Clicker Question For the reaction 2HF(g) H2(g) + F2(g), G° = 38.3 kJ, at 1000 K. If, at this temperature, 5.00 mol of HF(g), 0.500 mol of H2(g), and 0.75 mol of F2(g) are mixed in a 1.00-L container: a) Some HF will decompose (to yield H2 and F2). b) Some HF will be formed (from H2 and F2). c) The system is at equilibrium. d) Not enough data are given to answer this question. e) I do not know.

Clicker Question At 699 K, ∆G° = –23.25 kJ for the reaction H2(g) + I2(g) 2HI(g). Calculate ∆G for this reaction if the reagents are both supplied at 10.0 atm pressure and the product is at 1.00 atm pressure. a) –3.5 kJ b) –36.6 kJ c) +36.6 kJ d) –50.0 kJ e) +50.0 kJ

Clicker Question Consider the following system at equilibrium at 25°C: PCl3(g) + Cl2(g) PCl5(g). For the reaction as written, ΔG° = –92.50 kJ. When the temperature is raised the ratio of the partial pressure of PCl3(g) to the partial pressure of PCl5(g) will a) decrease. b) increase. c) not change. d) This is impossible to answer without additional information.

Clicker Question (slide 1/2) You transfer equal amounts of heat (1.00 kJ) to two separate samples of 1.00 mol of an ideal monatomic gas each at 25°C. One sample is in a steel tank, and the other is in a container fitted with a frictionless, massless piston. Compare ∆S for each. ∆S for the gas in the steel tank =   a) 1.10 J/K b) 1.83 J/K c) 2.97 J/K d) 3.11 J/K e) 4.95 J/K

Clicker Question (slide 2/2) You transfer equal amounts of heat (1.00 kJ) to two separate samples of 1.00 mol of an ideal monatomic gas each at 25°C. One sample is in a steel tank, and the other is in a container fitted with a frictionless, massless piston. Compare ∆S for each. ∆S for the gas in container fitted with the piston =   a) 1.10 J/K b) 1.83 J/K c) 2.97 J/K d) 3.11 J/K e) 4.95 J/K