Homework Check (Charles’s Law)

1. If I have a 0.25 L potato chip bag at a temperature of 19 ⁰C, and I leave it in my car which has a temperature of 60 ⁰C, what will the new volume of the bag be?

2. If I place a balloon with a temperature of 22 ⁰C and a volume of 0.5 L in my fridge, what will be the volume of the balloon when it is fully cooled by my fridge with a temperature of 4 ⁰C?

3. A gas at 89 ⁰C occupies a volume of 0.67 L. At what Celsius temperature will the volume increase to 1.12 L?

Gay-Lussac’s LawPRESSURE & TEMPERATURE

Pressure & Temperature Pressure: Force exerted by gas molecules colliding on the Area of the wall As Temperature rises, gas molecules move faster, thus colliding more on the wall → Pressure increases Volume (V) and number of gas molecules (n) are fixed

Gay-Lussac’s Law (P vs. T)As Temperature increases, Pressure increases; as T decreases, P decreases

Pressure is directly proportional to Temperature (K)

Examples1. If a child has a rigid ball with 25 atm of pressure at 22 ⁰C, what

will the pressure be at 0 ⁰C?

2. At 10 ⁰C, a gas exerts 0.95 atm of pressure. At what temperature (in Celsius) will it exert a pressure of 0.75 atm?

Practice! (on a separate piece of paper)

1. The pressure in a car tire is 1.88 atm at 25.0 ⁰C. What will be the pressure if the temperature increases to 37.0 ⁰C?

2. The pressure of the Oxygen gas inside a canister is 5.00 atm at 25.0 ⁰C. The canister is located at a camp high on Mount Everest. If the temperature there falls to –10.0 ⁰C, what is the new pressure inside the canister?

3. Helium gas in a 2.00 L cylinder is under 1.12 atm pressure. At 36.5 ⁰C, that same gas sample has a pressure of 2.56 atm. What was the initial temperature (in Kelvin) of the gas in the cylinder?