The Famous Dry Ice Bomb

Our final topic for the year was gas laws and for the final experiment we made dry ice bombs. One of the students had brought a small Coke bottle to use for the experiment so we half filled it with water, added some dry ice, put the lid on tight, placed it on the verandah outside the lab and retreated to a safe distance.

It seemed like nothing was happening so we started another activity and after about 10 minutes we heard a big bang. When we went out to look, we could see a few little bits of plastic but most of the bottle had disappeared. Then we looked up.

The bootle had gone straight up and was embedded into the ceiling. We took this photo because we thought people might not believe us.

If you want to know what made the bottle explode, do the calculations. We added about 20g of dry ice and it had an airspace of about 112 mL. That day, the temperature was about 25 degrees C and atmospheric air pressure about 101 kPa.