You accidentally left a 1 kg block of Swiss cheese out on th

You accidentally left a 1 kg block of Swiss cheese out on the counter overnight. It came from the refrigerator where its temperature was 45F. and you keep your apartment at a warm 75 degree F. Assuming that all of the heat transfer is between the cheese and the air in your apartment, determine the total entropy change once the cheese is in thermal equilibrium with the air.

Solution

We know,

dQ= mc_pT

Here, m= 1 Kg

         c_p = Not given

         T = T₂-T₁

               = 75-45

              = 30

dQ= 1×c_p× 30

    =30 c_p

Now, Change of entropy S = dQ/T

                                               = 30 c_p/ 75

                                               = 0.4 c_p [Answer]