Demonstrations are a cornerstone of chemistry outreach. We can illuminate the sometimes dry discussion of chemical concepts and reactions with practical and exciting examples. From dramatic exothermic reactions to color changes to ice cream made with liquid nitrogen, we've recorded many of our live demos right here for your use and enjoyment.
Hydrogen is the first element on the periodic table. The element itself forms into the gas H2. Just like other gasses, pressurized H2 can be used to propel a projectile. Since hydrogen is less dense than the surrounding air, greater compression can be achieved. Also, H2 molecules have a low mass and can travel faster than typical gas molecules (such as the main components of air, N2 and O2). These properties both increase the force that H2 cannons can impart onto projectiles! Unfortunately, the principals involved here did not improve our cannon's aim.
Nitrogen makes up the bulk of the gasses in our atmosphere. However, if you cool it down to -196ºC at 1 atm, it will liquify. Liquid N2 can rapidly cool and freeze materials, including food. With a few ingredients and a little elbow grease, liquid N2 can be used to make a tasty treat!
Cesium is an alkali metal that reacts violently when exposed to water. The metal will reduce the hydrogen atoms in water (H2O) to form H2 gas. This reduction reaction is highly exothermic, meaning that it generates heat. So we have H2 gas produced on a hot surface. Since the surrounding air contains plenty of O2, the H2 + O2 mixture will then ignite to produce water in a spectacular reaction!
Some combinations of metal and metal oxide powders can react to liberate tremendous amounts of energy. Since this is a solid-solid reaction, it usually requires a heat source for ignition. The most well-known of these is called the thermite reaction (Fe2O3 + 2 Al → 2 Fe + Al2O3), which can generate temperatures in excess of 2400ºC. That’s hot enough to melt most common metals or turn sand into glass slag!