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Dissipation of stored energy

  1. Sep 9, 2005 #1
    I have a question:

    2 glass containers have the same amount of a particular acid. In one container, drop a fully compressed spring retained in the compressed state by some means. In another container, drop a similar spring, in its free form. The acid in the containers start to dissolve the spring material. What happens to the stored energy in one of the spring, which was compressed earlier?
  2. jcsd
  3. Sep 9, 2005 #2
    interesting question. I have no idea. I kind of want to try this experiment out.
  4. Sep 9, 2005 #3


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    I would imagine that energy of the compressed spring is slowly dissipated, as opposed to a more irreversible processes. Think about what happens when the cross section of the springs becomes smaller, would the spring constant change? The thermodynamics of the acid reaction with the compressed spring will differ from an ordinary reaction (non-compressed spring), in the former you have more energy released, at the molecular level the atoms are somewhat more closer together, the PE is higher, similar to a situation in an organic molecule where you have a steric strain.

    Others may be able to give you a more official/detailed explanation, try one of the physics/quantum subforums.
  5. Sep 9, 2005 #4
    the energy would be dissipated as heat?
  6. Sep 9, 2005 #5


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    acid base reactions are exothermic at standard conditions (arrhenius acid base that is, and I do not know of any that are endothermic, consider the bond energies of products and reactants; so you'll need to consider a limited physical/engineering situation for endothermicity...), I would imagine that an acid base reaction with a compressed/"pressurized" molecular structure would be even more exothermic, yes I think it would be dissipated as heat. The network would have more PE associated with them due to strain probably.
  7. Sep 9, 2005 #6


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    Simply speaking, by compressing the spring you are changing the lattice energy for the metal. This will naturally affect the thermicity of the reaction as expected.

    (I agree with GCT : It's exactly the same as changing the PE by a steric strain.)
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