Core
Energetics: Enthalpy
Slide 9 of 34
Energy &
Kinetic Theory
Caloric
theory however was not able to explain every effect of heat, such as that
produced by friction.
In 1798 The American Benjamin Thompson
observed that if you rubbed to pieces of metal together you
could produced heat for as long as the pieces were being
rubbed.
If heat was a fluid found between atoms in the
substance, then the metal pieces should have produced less and
less heat over time as the fluid got lost.
Almost
half-a-century later James Joule demonstrated that mechanical energy could
be converted into an exactly equivalent amount of heat suggesting that
heat is a form of energy rather than an actual fluid.
In
the nineteenth century, scientists suggested that heat results from the motion
of particles of matter, called the kinetic theory
(about which we will have more to say when covering the topic
Kinetics).