Science Projects With Helium & Sulfur Hexafluoride

Measuring Gas

• Illustrate the weight differences between helium and sulfur hexafluoride in a project on measuring gas. Focus on capturing the gas to measure it. Fill three balloons with oxygen, helium and hexafluoride. Place one type of gas in each balloon. Measure the circumference of the balloon using a tailor's measuring tape (the cloth version) to ensure that each balloon is blown up to the same size. Observe the balloons after they are filled and record what this means about the weights of the gases. Explain why a balloon is needed in the experiment as well.

Weighing Gas

• Weigh the gases inside balloons created for the measuring gas projects by tying them to a fishing weight. Measure the weight first and deduct that measurement from the final weight given for each balloon. Use a food measurement scale for the best accuracy. Record your observations and measurements.

The Density Trick

• Capture the gas to complete this experiment. Use a toy or lightweight object like a foam ball to help illustrate the density of the gases. Two clear bowls of the same size will work for one container for the gas, as will a clear soft drink bottle. Put the bowls together so that the mouths meet to make a complete enclosure. Do this three times to make three containers. Place the ball inside each of three containers you plan to use for the experiment. Seal the bowls together. Seal the top of the soft drink bottle if that is your container. Make a hole to insert the gas, plugging the hole once you are finished. Put oxygen, helium or sulfur hexafluoride in each container. Keep your eyes on the toy or ball.

Sound Experiment

• Use oxygen, helium and sulfur hexafluoride to fill three balloons (one gas per balloon). Use a voice recorder to record the experiment. Inhale one quick breath from the first balloon. Speak a sentence or two while recording the sound. Say the name of the gas used as well. Do this twice more, taking several breaths between each balloon to get oxygen into your lungs. Failing to do so can lead to hypoxia, as the helium and sulfur hexafluoride take the place of oxygen when you breathe it in. Make your observations about the effects of each gas on the sound emitted from your voice. The denser gas slows the sound and the less dense gas will allow the sound to escape faster than air.