Warm-Up: To be turned in Consider the following three containers filled with the same gas at the indicated pressures: If all three containers have the same volume and are at the same temperature, which has the most molecules? Explain your answer. 1atm 2atm 3 atm

Gay-Lussac’s Law

Joseph-Louis Gay-Lussac 1778-1850 French chemist and physicist Pioneered investigations into the behavior of gases

Gay-Lussac’s Law At constant volume, pressure and temperature are directly related. As one goes up, so does the other one Can be explained with kinetic molecular theory. As temperature increases, the molecules moves faster, leading to more collisions against the container, increasing pressure.

P1 = P2 T1 T2 P1= initial pressure T1= initial temperature* P2= final pressure T2= final temperature* *temperature must be in Kelvin scale! K= °C+273

A gas in an aerosol can is at a pressure of 3. 00atm at 25°C A gas in an aerosol can is at a pressure of 3.00atm at 25°C. What would the pressure be if the temperature was raised to 52°C? P1 = P2 T1 T2 3.00 = P2 298 325 975 = 298P2 298 298 3.27atm= P2

Before a trip from New York to Boston, the pressure in an automobile tire is 1.8 atm at 20.°C. At the end of the trip, the pressure gauge reads 1.9 atm. What is the new temperature of the air inside the tire? P1 = P2 T1 T2 1.8 = 1.9 293 T2 556.7 = 1.8T2 1.8 1.8 309K= T2

At 120. °C, the pressure of a sample of nitrogen is 1. 07 atm At 120.°C, the pressure of a sample of nitrogen is 1.07 atm. What will the pressure be at 205°C, assuming constant volume? P1 = P2 T1 T2 1.07 = P2 393 478 511.46 = 393P2 393 393 1.30atm= P2