Crumpled bottle

The heat from a chemical reaction rapidly deforms a plastic bottle!

5 minutes
Crumpled bottle



  • Put on protective gloves and eyewear.
  • Conduct the experiment on the plastic tray.
General safety rules
  • Do not allow chemicals to come into contact with the eyes or mouth.
  • Keep young children, animals and those not wearing eye protection away from the experimental area.
  • Store this experimental set out of reach of children under 12 years of age.
  • Clean all equipment after use.
  • Make sure that all containers are fully closed and properly stored after use.
  • Ensure that all empty containers are disposed of properly.
  • Do not use any equipment which has not been supplied with the set or recommended in the instructions for use.
  • Do not replace foodstuffs in original container. Dispose of immediately.
General first aid information
  • In case of eye contact: Wash out eye with plenty of water, holding eye open if necessary. Seek immediate medical advice.
  • If swallowed: Wash out mouth with water, drink some fresh water. Do not induce vomiting. Seek immediate medical advice.
  • In case of inhalation: Remove person to fresh air.
  • In case of skin contact and burns: Wash affected area with plenty of water for at least 10 minutes.
  • In case of doubt, seek medical advice without delay. Take the chemical and its container with you.
  • In case of injury always seek medical advice.
Advice for supervising adults
  • The incorrect use of chemicals can cause injury and damage to health. Only carry out those experiments which are listed in the instructions.
  • This experimental set is for use only by children over 12 years.
  • Because children’s abilities vary so much, even within age groups, supervising adults should exercise discretion as to which experiments are suitable and safe for them. The instructions should enable supervisors to assess any experiment to establish its suitability for a particular child.
  • The supervising adult should discuss the warnings and safety information with the child or children before commencing the experiments. Particular attention should be paid to the safe handling of acids, alkalis and flammable liquids.
  • The area surrounding the experiment should be kept clear of any obstructions and away from the storage of food. It should be well lit and ventilated and close to a water supply. A solid table with a heat resistant top should be provided
  • Substances in non-reclosable packaging should be used up (completely) during the course of one experiment, i.e. after opening the package.

FAQ and troubleshooting

The contents of the vial ended up everywhere. How should I clean them up?

Make sure that the vial has cooled down. Check the thermosticker: if the triangle is black, you can safely touch the vial. Be sure to wear protective gloves! If any powder has spilled onto the tray, simply rinse the tray with water. And if any has spilled onto the table, carefully sweep the powder off onto a sheet of paper and thoroughly clean the table with a cloth.

There is steam coming from the vial! Is everything okay?

This is just aqueous vapor from the water you added. Be careful, though: steam can be hot! DO NOT under any circumstances bend over the vial to take a look inside.

The thermosticker peeled off when the bottle deformed. How can I be sure that the bottle is safe to touch?

Leave the bottle on the tray and wait. After one or two hours, the bottle will cool down completely and you will be able to safely clean everything up.

Step-by-step instructions

The reaction you are going to see can be pretty violent, so be sure to perform it on the tray.


Water H2O reacts with calcium oxide CaO, yielding calcium hydroxide Ca(OH)2 and a lot of heat!



Dispose of solid waste together with household garbage.

Scientific description

Can you think of anything safer than a few drops of water? Just think—even something so seemingly harmless can cause a violent reaction! Just like in this experiment, where water H2O reacts with calcium oxide CaO to make Ca(OH)2 and lots and lots of heat.


While any chemical reaction releases or absorbs some amount of heat, it’s particularly easy to figure out where this energy comes from with quicklime. The reaction you just observed is part of a series of reactions called “the limestone cycle.” It all begins with limestone, which is mostly calcium carbonate CaCO3. If you give CaCO3 a lot of heat energy, it decomposes into CO2 and CaO. The CaO holds on to some of the energy, which can be released in the reaction with water you just saw. Ca(OH)2 then reacts with CO2 to make CaCO3, completing the cycle.


Why would anybody go to the trouble of heating and changing CaCO3 just to seemingly end up where they started? Limestone CaCO3 is a decent construction material, but it’s pretty hard to carve separate stones to fit perfectly together—it’s much more convenient to make CaCO3 form directly in the spaces between the stones. And that’s exactly how lime mortar works! The Ca(OH)2 in mortar slowly turns into the much stronger CaCO3