Why does a bicycle tyre get hot when inflated

A bicycle tyre gets quite hot during its inflation. The work of inflating the tyre explains in part why the temperature increases, but careful calculations (e.g. see pp. 86 and 89) show that additional factors are responsible for the rise in temperature. 

On a macroscopic level, we say we compress the gas into the confined space within the tyre on a microscopic level, interparticle interactions form as soon as the gas particles come into close proximity. 

We look on p. 86 at the effect of performing work while inflating a bicycle tyre, and the way work impinges on the internal energy of the gas. 

All matter seeks to minimize its energy and entropy see Chapter 4. This concept explains, for example, why a ball rolls down a hill, and only stops when it reaches its position of lowest potential energy. These interparticle interactions form for a similar reason. 

When we say that two atoms interact, we mean that the outer electrons on the two atoms respond to each other. The electrons within the inner orbitals are buried too deeply within the atom to be available for interactions or bonding. We indicate this situation by saying the electrons that interact reside within the frontier orbitals. 

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