RP8-Boyle's and Charles' laws

• Boyle's law equipment: Stand, clamp, syringe, clip, mass holder, masses, rubber tubing.
• Boyle's law set up: Attach the syringe facing upwards to the stand with rubber tubing and a clip sealing the open end. With the plunger removed, measure the internal diameter then reinsert plunger and attach the mass holder to the plunger.
• Boyle's law method: Move the plunger up and down to prevent sticking and add a mass. Record the new volume on the syringe. Continue to add masses and record the volume. Repeat the whole experiment twice more and calculate a mean volume for each mass.
• Boyle's law graph: Plot a graph of pressure against 1/volume. A straight line through the origin should be obtained.
• Boyle's law analysis: Calculate the pressure using P = F/A = m g/A. Then subtract this from standard atmospheric pressure: 101 kPa.
• Boyle's law safety: The stand could topple - use a clamp or counterweight.
• Charles' law equipment: Capillary tube, sulfuric acid, beaker, heat proof mat, thermometer, kettle, ruler.
• Charles' law set up: Submerge the capillary tube in hot water in a beaker, ensuring it covers the air sample but doesn't go over the top (since the capillary tube is open at the top). Line up a ruler behind the capillary tube, and attach if necessary.
• Charles' law method: Stir the water and measure the temperature and length of the air sample on the ruler. Repeat this as the water cools every five degrees down to room temperature. Repeat twice more and find a mean length.
• Charles' law graph: Plot a graph of length against temperature.
• Charles' law analysis: Absolute zero can be found by doing temperature - length/gradient, where the temperature and length values are a pair on the line of best fit.
• Charles' law safety: The sulfuric acid in the capillary tube can cause irritation and eye damage - wear goggles and don't touch if spilled; boiling water can cause burns - keep beaker away from edge of table, don't touch.