• Question: What elements are highly explosive if in contact with each other ??????

    Asked by Thea ferley to Gavin, Karen, Mark, Michel, Roisin on 12 Nov 2016.
    • Photo: Mark Kennedy

      Mark Kennedy answered on 12 Nov 2016:


      There are tonnes of combinations that are explosive when they come in contact with each other. There’s a very good video here showing how even hydrogen (the most basic element in the Universe) is explosive: https://www.youtube.com/watch?v=z7-8gxAXXbU .

      My favourite from school was when my teacher would add small amounts of potassium to water – perhaps you could ask one of your teachers to show you this as a demonstration?

    • Photo: Karen

      Karen answered on 13 Nov 2016:


      There are as Mark says a huge amount of explosive reactions between elements. Here is a link to 10 explosive reactions http://io9.gizmodo.com/5886602/ten-amazing-and-occasionally-explosive-chemical-reactions-caught-on-video . One of the most powerfully explosive chemicals known to man is a compound called PETN, a substance similar to nitroglycerine which is used to make semtex bombs amongst other weapons.
      The least explosive elements as the noble or inert gases, argon, xenon, neon, helium etc and they have very little reactivity with anything.

    • Photo: Roisin Jones

      Roisin Jones answered on 13 Nov 2016:


      Oh there are so so many! Any of the alkali metals (like the potassium that Mark mentioned) are flammable or explosive in contact with water. There are a number of very strong bases, such as a substance called tert-BuLi which can be explosively flammable on contact with air or water. Glucose and potassium chlorate are another explosively flammable combination!

      In general, nitro containing compounds such as the PETN that Karen mentioned, along with TNT (not the same thing as dynamite, though they are often used interchangeably) and RDX (the active component in C4) are highly explosive, though they often need a trigger (or detonator) to get them going. Other compounds such as azides, some peroxides and pure nitroglycerin are what are known as ‘contact explosives’, which means that a physical shock will cause them to explode.

Comments