Science, Tech, Math › Science Hydrogen Balloon Explosion Experiment Share Flipboard Email Print Science Chemistry Projects & Experiments Basics Chemical Laws Molecules Periodic Table Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated June 04, 2020 One of the most impressive chemistry fire demonstrations it the hydrogen balloon explosion. Here are instructions on how to set up the experiment and perform it safely. Materials small party balloonhydrogen gascandle taped to the end of a meter sticklighter to light the candle 01 of 03 The Chemistry Use a long torch or candle attached to a meter stick to detonate a hydrogen balloon! This is one of the most dramatic chemistry fire demonstrations. Anne Helmenstine Hydrogen undergoes combustion according to the following reaction: 2H2(g) + O2(g) → 2H2O(g) Hydrogen is less dense than air, so a hydrogen balloon floats in much the same way as a helium balloon floats. It's worth pointing out to the audience that helium is not flammable. A helium balloon will not explode if a flame is applied to it. Further, although hydrogen is flammable, the explosion is limited by the relatively low percentage of oxygen in the air. Balloons filled with a mix of hydrogen and oxygen explode much more violently and loudly. 02 of 03 Perform the Exploding Hydrogen Balloon Demo Fill a small balloon with hydrogen. Don't do this too far in advance, since hydrogen molecules are small and will leak through the wall of the balloon, deflating it in a matter of hours.When you are ready, explain to the audience what you are going to do. While it's dramatic to do this demo by itself, if you want to add educational value, you can perform the demo using a helium balloon first, explaining that helium is a noble gas and therefore unreactive.Place the balloon about a meter away. You may wish to weight it to keep it from floating off. Depending on your audience, you might want to warn them to expect a loud noise!Stand a meter away from the balloon and use the candle to explode the balloon. 03 of 03 Safety Although it is easy to produce hydrogen gas in the lab, you'll want compressed gas to fill the balloon. This demonstration should only be performed by an experienced science teacher, demonstrator or scientist. Wear the usual protective gear, such as goggles, lab coat, and gloves. This is a safe demonstration, but it's advisable to use a clear blast shield for any fire-related demonstrations.