(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

0.5 kg of water at a temperature of 5.6 oC is mixed with 1.3 kg of alcohol at 65.9 oC. They come to equilibrium. What is the change in entropy (in J/K) of the system when the two liquids are mixed?

Hint:

The specific heat capacity for water is 1 kcal/kgoC = 4186 J/(kgoC), and for alcohol it is 0.58 kcal/kgoC = 2430 J/kgoC.

2. The attempt at a solution

I calculate Tf = [m1c1T1+m2c2T2] / [(m1c1) + (m2c2)] = 41.87*C

then Delta S = m1c1 ln(Tf/T1) + m2c2 ln (Tf/T2) = 2778 J/C

Then I convert to J/K which is devide it by 274.15 = 10.13 J/K = INCORRECT!!!

This is a messy problem. Please help!!!

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# Homework Help: Change in entropy problem

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