British Sign Language Glossaries of Curriculum Terms

BSL Chemistry Glossary - exothermic - Laboratory video

Note: this is a long clip so please allow it time to load.

This is a nice example of a reaction. It is different because it is an exothermic reaction where a great deal of heat is given out.

What I have here is Aluminium (Al) which will react with the Iodine (I₂). I am going to mix the two together and then empty it onto a heat-proof mat then when I add a few drops of water watch what happens - there will be an exothermic reaction. What you saw there was the Al reacting very rapidly with the I₂ and as it does so the reaction gives off heat - that is an example of an exothermic reaction.