If an aluminum bar is temporarily joined among a hot reservoir at 720 K and a cold reservoir at 368 K, 2.20 kJ of energy is transferred through heat from the hot reservoir to the cold reservoir.
(i) In this irreversible procedure, compute the change in entropy of the hot reservoir.
(ii) In this irreversible procedure, compute the change in entropy of the cold reservoir.
(iii) In this irreversible procedure, compute the change in entropy of the Universe, avoiding any change in entropy of the aluminum rod.
(iv) Mathematically, why did the outcome for the Universe in part (iii) encompass to be positive?