The Colorado School of Mines members of the American Chemical Society did their best to show students the fun side of chemistry through fire, explosions, and free food.
The ACS members started out the night with a Magnesium Lantern demonstration, which involved lighting a pile of magnesium and surrounding it with dry ice. The magnesium remained lit for a short time while covered by dry ice. This experiment demonstrated how “hungry” magnesium is for oxygen and how useful it is for providing bright light in unusual or environments with low oxygen levels. The following demonstration lit ice on fire using the reaction between ice and solid Calcium Carbide to produce flammable acetylene gas. Next, the ACS members set up an oscillating clock reaction, which involved mixing chemicals in such a way that the solution of the reaction switched periodically between four colors. After that demonstration, the ACS members filled a 2 liter soda bottle about a quarter of the way with liquid nitrogen and set this contraption aside inside a protective explosion box.
As the bottle of liquid nitrogen expanded from the heat of the room going into the nitrogen and changing it from a liquid into a gas, the ACS members delighted the pyromaniacs in the room by bringing out a thermite demo. This involved mixing and lighting iron oxide and aluminum powder in a funnel inside a flower pot above a beaker of water, which resulted in a large flame and the formation of molten iron. Afterwards, the chemists brought out a series of chemicals that glowed in the dark when mixed together, although it did not stay luminescent for long. Around this time, the pressure of the expanding gases in the bottle of nitrogen became too much for the plastic to bear and it exploded with a violent bang.
The chemists then proceeded to dip various objects into a vat of liquid nitrogen, including a racquetball (which was promptly thrown and shattered) and several bananas and apples, which were broken into pieces and given to the audience. In quick succession, the ACS members set off nitrogen triiodide, which is an easy to make explosive that can be set off with a very light touch and makes a loud bang when it goes off, but does not cause a whole lot of damage.
The chemists moved on to the finale by filling one balloon with a mixture of hydrogen and oxygen and another with pure hydrogen. The former produced a loud explosion while the latter resulted in the balloon getting engulfed in flames. The chemists ended the demonstration by making chocolate and vanilla ice cream for the whole audience using liquid nitrogen. Not all of the demonstrations worked perfectly, but as the ACS members kept reminding the audience, “Chemistry is an experimental science,” and after all, the ice cream was delicious.