Do all gases expand by the same amount when you heat them? You might expect helium to expand the most since it fills party balloons so well. The real ranking is surprising.
You fill Mylar balloons with five different gases and seal two balloons per gas. Each balloon is submerged in water at temperatures from 1°C to 60°C. You measure the water displaced by each balloon to track volume changes.
Oxygen expanded the most with a 36.5% volume increase. Carbon dioxide expanded the least at 15.3%. Helium finished fourth, not first. The gas that lifts balloons best is not the one that expands most with heat.
Hypothesis
The hypothesis is that helium at 60°C or lower will have more volume than any of the other gases at the same temperature or lower.
When you heat a gas, it gets bigger — but different gases expand by different amounts. Five gases sealed in Mylar balloons are submerged in water as the temperature rises from 1°C to 60°C. You measure the water displaced by each balloon to track volume changes. Oxygen expanded the most, with a 36.5% volume increase. Carbon dioxide expanded the least at 15.3%. Helium, which fills party balloons so well, finished fourth — not first.
Heat changes the space a gas fills — but not all gases expand by the same amount. You fill Mylar balloons with five different gases and submerge each one in water at temperatures from 1°C to 60°C, measuring the water displaced to track volume changes. Oxygen expanded the most at 36.5%. Carbon dioxide expanded the least at 15.3%. Helium, which lifts party balloons so well, finished fourth — not first.
Method & Materials
You will fill 10 Mylar balloons with different gases, attach them to a bucket, and submerge them in water at different temperatures. You will measure the volume of each gas and record the data.
You will need a bucket, fishing line, a graduated cylinder, a beaker, a thermometer, 10 Mylar balloons, a cap, an S-hook, silicone, a pipe, eye bolts, and a piece of tubing.
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The results indicate that as the temperature of any gas was increased, the volume would also increase. Oxygen had an overall percentage volume change of 36.5%, nitrogen changed 21.8%, argon had a 20.5% change, helium had a 16.4% change, and carbon dioxide changed 15.3%.
Why do this project?
This science project is interesting because it shows how different gases expand when heated, which can be useful for understanding how to use different gases in balloons.
Also Consider
Experiment variations to consider include using a different size balloon and adding something to the water like salt.
Full project details
Additional information and source material for this project are available below.
