More generally the work available relative to some ambient is obtained by multiplying ambient temperature T o by relative entropy or net surprisal Δ Δ I ≥ ≥ 0 , defined as the average value of k ln ⁡ ⁡ ( p / p o ) where p o is the probability of a given state under ambient conditions. For instance, the work available in equilibrating a monatomic ideal gas to ambient values of V o and T o is thus W = T o Δ Δ I , where relative entropy