Question

In: Mechanical Engineering

Two kilograms of air is stored in a rigid volume of 2 m3 with the temperature...

Two kilograms of air is stored in a rigid volume of 2 m3 with the temperature initially at 300°C. Heat is transferred from the air until the pressure reaches 120 kPa. Calculate the entropy change of (a) the air and (b) the universe if the surroundings are at 27°C.

Solutions

Expert Solution

First, the entropy change of system is calculated then the entropy change of surroundings is calculated using heat transfer from the system. This is used to calculate the change in entropy of the Universe.

(a) Entropy change of air " (Sair) = -0.2263 kJ/kg.K or -0.4526 kJ/K ".

(b) Entropy change of universe " (Suniverse) = 0.2884 kJ/K ".

samet mamat answered 11 months ago
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