Why would a substance solidify as it heats up?

Discussion in 'Chemistry' started by Magical Realist, Apr 22, 2014.

  1. Magical Realist Valued Senior Member

    Messages:
    11,108
    Example: eggs.
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Kittamaru Never cruel nor cowardly... Staff Member

    Messages:
    13,651
    Chemistry!

    Other than that... honestly, I'm not sure what the exact processes are. A quick google search:

    The reason why the eggs turn solid when cooked is because they are made up of lots of proteins. When the proteins of a raw, liquid egg come into contact with heat, it causes them to change form. The reason they change is due to the heat that makes the individual units of protein link together differently into what are ultimately stronger chains.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Magical Realist Valued Senior Member

    Messages:
    11,108
    That's interesting. A kind of self-organizing matrix of proteins then. Chains linked to chains resulting in a sunny side up miracle.
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. exchemist Valued Senior Member

    Messages:
    6,855
    From what I read, this is an example of a curing process: http://en.wikipedia.org/wiki/Curing_(chemistry)

    The proteins in raw egg white are long chains curled up into balls. Heating make the balls uncoil, and then the unravelled long chains form chemical bonds from one to another, thus linking them all into a bound network. Some glues and resins do a similar thing though often initiated by something than than heat.

    The key thing, as Kittimaru commented originally, is that this is a chemical change rather than a simple change of physical state.
     
  8. Kittamaru Never cruel nor cowardly... Staff Member

    Messages:
    13,651
    *nods* It's funny... for as much as we (as a species) know about the world around us... we know precious little... and even less about the "why" of so many things.
     
  9. Janus58 Valued Senior Member

    Messages:
    1,847
  10. Magical Realist Valued Senior Member

    Messages:
    11,108
    From article:

    "Pouring egg whites into a beaker of acetone will also turn egg whites translucent and solid."

    That's interesting, though I wouldn't exactly serve it for breakfast.
     
  11. exchemist Valued Senior Member

    Messages:
    6,855
    And as you may know, you can "cook" fish by marinating it in lemon juice (e.g. ceviche) or vinegar (soused herrings etc). Very tasty, too. So proteins can be denatured by a variety of means.
     

Share This Page