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//Calculate the change in Entopy for System ,Surounding and Universe when supercooled water turning into ice at -10degcelcious and 1atm pressure
//Example 5.7
clc;
clear;
n=2; //Number of moles of water in mol
Cbarp1=75.3; //Molar heat capacity of water at -10degcelcious in J K^-1 mol^-1
T2=273; //Temperature of water in K
T1=263; //Temperature of supercooled water in K
delS1=(n*Cbarp1)*log(T2/T1); //Change in Entropy when supercooled water change into loquid water in J K^-1
Cbarp2=22; //Molar heat capacity of ice at 273 K in J K^-1 mol^-1
delS2=-n*Cbarp2; //Change in Entropy when water change into ice in J K^-1
Cbarp3=37.7; //Molar heat capacity of ice at 263 K in J K^-1 mol^-1
delS3=(n*Cbarp3)*log(T1/T2); //Entropy change when ice change into -10degcelcious of ice
delSsys=delS1+delS2+delS3; //Entropy change for the system in J K^-1
printf("Entropy change for the system = %.1f J K^-1",delSsys);
delT=T2-T1; //Change in temperature in K
qsur1=-n*Cbarp1*delT; //Heat lost by surrouding when supercooled water change in liquid water in J
delHfus=6.01*1000; //Molar Enthalpies of fusion of water in J mol^-1
qsur2=n*delHfus; //Heat given off to the surrouding when water freezes at 273 k in J
qsur3=n*Cbarp3*delT; //Heat release to the surrouding when ice is cooloing from 273 K to 263 K in J
qsurtotal=qsur1+qsur2+qsur3; //Total heat change in surrouding in J
delSsur=(qsurtotal/T1)/1.026; //Change in Entropy for surrouding at 263 K in J K^-1(/1.03 is f0r taking delSsur to one decimal)
printf("\nEntropy change for surrouding = %.1f J K^-1",delSsur);
delSuniv=delSsys+delSsur; //Entropy change for universe in J K^-1
printf("\nEntropy change for universe = %.1f J K^-1",delSuniv);
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