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1kg. Water (at 30oC) is mixed with 2kg. Water (at OoC) calculates the change in entropy |
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Answer» Let the final temperature reached be t℃ Specific heat capacity of water = c = 1000 J kg− ℃− Given masses = 1 kg and 2 kg Respective temperatures = 30℃ and 0℃ By zeroth law of Thermodynamics, Heat lost by 0℃ water = Heat gained by 0℃ water i.e. 1 × c × (30-t) = 2 × c ×(t-0) 30 - t = 2t 30 = 3t t = 10 Change in entropy of 30℃ water = {1×1000×(10–0)}/(10+273) = 35.33 j/k Change in entropy of the 0℃ water = -{(2×1000×(30–10)}/(10+273) = 212.01 j/k However the net change in the entropy of the total system(of 30℃ water and 0℃ water) = 35.33 - 212.01 j/k = 176.88 j/k |
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