Find the difference in entropy between a cup of water and a cup of ice for each of these cases: 1. both are at T=0C 2. ice is at T=0C water is at 20C ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ If the "water" is at 0C then it is ice right? and the difference in entropy is 0 correct? For the second part... do you think I am supposed to find the Q for each one? since the equation for Q is Q=cmT I don't think this would make sense because the equation for entropy (S) is S=Q/T. For ice it would be 0/0 and you can't do that.... Do you think maybe he's asking for the change in entropy if you mix the two together? Thanks. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ EDIT I just remembered the equation is Q=cmdeltaT So this must mean that he does want to know the change of entropy in the system if you mix the two together??