  We focus attention on some particular thermodynamic relations (PTR). Using
information theory concepts we show that, for a reversible process, microscopic
considerations related to these PTR make the concomitant informational contents
of the first and second laws equivalent. The pertinent demonstration is
obtained when trying to ascertain the corresponding equilibrium microscopic
probability distribution. We also describe other instances in which the above
mentioned informational equivalence does not hold.
