Announcements Exam #1: Tuesday, September 24th, 7:00-8:15pm, locations on website Conflict Exam: 5:15-6:30pm, 103 Transportation Bldg, sign up outside of 101 CA until noon on 9/24 Review Questions for Exam 1 due tomorrow by 5:00pm

Q & A Review Sessions Now posted on course website under Exam Information

Kinetic Molecular Theory Gases are made of particles in constant random motion. Temperature is a measure of random kinetic energy. Pressure is due to collisions of gas particles with the container.

KMT (assumptions) Assume that gas particles exert no attractive forces (elastic collisions). Assume the volume of the gas particles is negligible (zero).

Clicker #1 The two balloons above are the same size but contain different gases. How do the pressures inside the balloons compare? A) The pressures are the same. B) The balloon with helium (He) has the greater pressure. C) The balloon with xenon (Xe) has the greater pressure. D) Not enough information is given to answer this question. He Xe

Clicker #2 The two balloons above are the same size but contain different gases. Which gas particles will hit the walls of the balloon harder? A) They both hit with the same amount of force. B) The helium particles will hit harder. C) The xenon particles will hit harder. He Xe

Clicker #3 You are holding three balloons each containing the same mass of gas. One balloon contains hydrogen gas, one contains helium, and one contains oxygen. Which balloon is the largest? A) The hydrogen balloon is the largest. B) The helium balloon is the largest. C) The oxygen balloon is the largest. D) All of the balloons are the same size.

Here are some additional problems that we didn’t get to in lecture… A 50.0-L steel tank contains 186 mol N2 and 145 mol O2 at 24oC. What is the partial pressure of each gas in the tank? What is the total pressure in the tank?

Consider a sample of gas at 2.00 atm in a 35.0-L container at 25.0oC. You transfer all of the gas to a 70.0-L container and you heat the gas to 50.0oC. Determine the new pressure of the gas.

Consider a sample of gas at 5. 40 atm in a 1 Consider a sample of gas at 5.40 atm in a 1.00-L rigid container at 40.0oC. You heat the gas to 80.0oC. What happens? Solve for the new condition.

Consider a sample of gas at 5. 40 atm in a 1 Consider a sample of gas at 5.40 atm in a 1.00-L container fitted with a piston at 40.0oC. You heat the gas to 80.0oC. What happens? Solve for the new condition.