Charles’s Law: The Effect of Temperature on Name______Volume Period______According to the kinetic theory, an increase in temperature will cause the molecules of a gas to move faster and exert more pressure, or cause the gas to expand. Conversely, as a gas is cooled, the molecules will move more slowly and the gas will contract, or exert less pressure. In other words, the volume of a gas increases as temperature increases if the pressure remains constant. This relationship between the volume of a gas and its temperature is known as Charles’s Law. In this experiment you will study the effects of temperature on gas volume and determine the constant for the relationship, V/T.

Objectives: In this experiment, you will  Determine the effect of temperature on the volume of a gas when pressure is constant,  Use your volume and temperature data to calculate the relationship between these values

Equipment 1. Goggles 5. One Hole Stopper 9. Hot Plate 2. Beaker 6. Glass tubing 10. Thermometer 3. Erlenmeyer flask 7. Utility Clamp 11. Graduated Cylinder 4. Towel 8. Deep Sink Procedure 1. Measure the total volume of your Erlenmeyer flask by filling with water and placing the rubber stopper in the opening. Pour this water into the graduated cylinder to find the total volume of the entire flask. This will require you to fill up the 100mL graduated cylinder multiple times, adding all the volumes. 2. Setup the apparatus as shown in the figure below.

Add enough water to the beaker, so that the beaker is close to full. Place a one hole stopper fitted with a 3cm glass tube on the flask, and place the flask as shown in the figure on the back. Bring the water to a boil for 5 minutes and

record the temperature with the Thermometer as T1 in your data table. 3. Remove the Flask by loosening the clamp from the ring stand. Have your finger plugging the glass tubing as you do this. Flask into the one of the three different temperature sinks. Record the temperature of this sink water using your thermometer. This is T2. 4. Remove finger form end of stopper and hold flask while it cools. When cooled, water will stop being pushed into the flask. Raise the flask upside down so that the water level inside the flask and the sink are level. The Atmospheric pressure inside the flask is now equal to the pressure outside 5. Place your finger over the glass tubing and remove the flask from the water. Place it on your table in an upright position before removing finger. Remove the stopper and record the volume of the water in the flask using the

graduated cylinder. Subtract volume of water from volume of entire flask to find volume of gas = V2. 6. Repeat this for other two different temperatures. Cold water should have the smallest volume, warm the most.

DATA TABLE

Temperature of hot air (T1) in Kelvin.

Volume of the entire flask with rubber stopper in = hot air (V1)

Temperature of warm water in Kelvin (T2). Volume of water pushed into the flask in warm water.

Total volume of gas in flask after water was pushed in. (V2)

Temperature of room temp water in Kelvin (T3). Volume of water pushed into the flask in room temp water. Volume of gas in flask after water was pushed in.

Temperature of cold water in Kelvin (T4). Volume of water pushed into the flask in cold water. Volume of gas in flask after water was pushed in. Questions 1. Create a graph of Temperature(x axis) vs. Volume(y axis). Include 0 K has 0 mL volume in this graph.

2. Every calculation should have the same value. Explain why using Charles law:

V1 V2 V3 V4 = = = T1 T2 T3 T4 3. Show your work for calculating your slope. Use the best two points to support Charles Law.

4. As you temperature decreased, explain what happened to your volume and why (on a particle level)?