{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 18:Entropy, Free Energy,and Equilibrium" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.2,Page no:809" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "#(a)\n", "SCaO=39.8 #standard entropy of CaO, J/K mol\n", "SCO2=213.6 #standard entropy of CO2, J/K mol\n", "SCaCO3=92.9 #standard entropy of CaCO3, J/K mol\n", "#(b)\n", "SNH3=193 #standard entropy of NH3, J/K mol\n", "SN2=192 #standard entropy of N2, J/K mol\n", "SH2=131 #standard entropy of H2, J/K mol\n", "#(c)\n", "SHCl=187 #standard entropy of HCl, J/K mol\n", "SH2=131 #standard entropy of H2, J/K mol\n", "SCl2=223 #standard entropy of Cl2, J/K mol\n", "\n", "#Calculation\n", "#(a)\n", "deltaSrxn1=SCaO+SCO2-SCaCO3 #standard entropy change of the reaction, J/K mol\n", "#(b)\n", "deltaSrxn2=2*SNH3-(SN2+3*SH2) #standard entropy change of the reaction, J/K mol\n", "#(c)\n", "deltaSrxn3=2*SHCl-SH2-SCl2 #standard entropy change of the reaction, J/K mol\n", "\n", "#Result\n", "print\"(a) the standard entropy of reaction is :\",deltaSrxn1,\"J/K mol\"\n", "print\"(b) the standard entropy of reaction is :\",deltaSrxn2,\"J/K mol\"\n", "print\"(c) the standard entropy of reaction is :\",deltaSrxn3,\"J/K mol\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a) the standard entropy of reaction is : 160.5 J/K mol\n", "(b) the standard entropy of reaction is : -199 J/K mol\n", "(c) the standard entropy of reaction is : 20 J/K mol\n" ] } ], "prompt_number": 22 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.4,Page no:817" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "#(a)\n", "GCO2=-394.4 #free energy of formation of CO2, kJ/mol\n", "GH2O=-237.2 #free energy of formation of H2O, kJ/mol\n", "GCH4=-50.8 #free energy of formation of CH4, kJ/mol\n", "GO2=0 #free energy of formation of O2, kJ/mol\n", "#(b)\n", "GMg=0 #free energy of formation of Mg, kJ/mol\n", "GMgO=-569.6 #free energy of formation of MgO, kJ/mol\n", "GO2=0 #free energy of formation of O2, kJ/mol\n", "\n", "#Calculation\n", "deltaGrxn1=(GCO2+GH2O*2)-(GCH4+2*GO2) #standard free energy change of the reaction, kJ/mol\n", "deltaGrxn=(GO2+GMg*2)-(2*GMgO) #standard free energy change of the reaction, kJ/mol\n", "\n", "#Result\n", "print\"(a) The standard free energy change of reaction is :\",deltaGrxn1,\"kJ/mol\"\n", "print\"(b) The standard free energy change of reaction is :\",round(deltaGrxn),\"kJ/mol\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a) The standard free energy change of reaction is : -818.0 kJ/mol\n", "(b) The standard free energy change of reaction is : 1139.0 kJ/mol\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.5,Page no:820" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "#for fusion\n", "T1=5.5+273 #temperature of fusion, K\n", "deltaH1=10.9*1000 #change in enthalpy, J/mol\n", "#for vaporisation\n", "T2=80.1+273 #temperature of vaporisation, K\n", "deltaH2=31*1000 #change in enthalpy, J/mol\n", "\n", "#Calculation\n", "deltaSf=deltaH1/T1 #since in fusion deltaG=0, J/ K mol\n", "deltaSv=deltaH2/T2 #since in vaporisation deltaG=0, J/ K mol\n", "\n", "#Result\n", "print\"The entropy change for fusion is\",round(deltaSf,1),\"J/K.mol\" \n", "print\"The entropy change for condensation is : \",round(deltaSv,1),\"J/K mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The entropy change for fusion is 39.1 J/K.mol\n", "The entropy change for condensation is : 87.8 J/K mol\n" ] } ], "prompt_number": 24 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.6,Page no:823" ] }, { "cell_type": "code", "collapsed": false, "input": [ "T=298 #temperature, K\n", "R=8.314 #gas constant, J/K mol\n", "GH2=0 #free energy of formation of H2, kJ/mol\n", "GH2O=-237.2 #free energy of formation of H2O, kJ/mol\n", "GO2=0 #free energy of formation of O2, kJ/mol\n", "\n", "#Calculation\n", "import math\n", "deltaG=1000*(2*GH2+GO2-2*GH2O) #free energy of rxn, J/mol\n", "Kp=math.exp(-deltaG/(R*T)) #equilibrium constant for rxn\n", "\n", "#Result\n", "print\"deltaG_rxn=\",deltaG/1000,\"kJ/mol\"\n", "print\"The equilibrium constant for the given reaction is :%.e\"%Kp" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "deltaG_rxn= 474.4 kJ/mol\n", "The equilibrium constant for the given reaction is :7e-84\n" ] } ], "prompt_number": 25 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.7,Page no:824" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "T=298 #temperature, K\n", "R=8.314 #gas constant, J/K mol\n", "Ksp=1.6*10**-10 #solubility constant\n", "\n", "#Calculation\n", "import math\n", "deltaG=-R*T*math.log(Ksp) #here solubility product is equal to equilibrium constant\n", "\n", "#Result\n", "print\"The free energy for the given reaction is :\",round(deltaG*10**-3),\"kJ/mol\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The free energy for the given reaction is : 56.0 kJ/mol\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example no:18.8,Page no:825" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "T=298 #temperature, K\n", "R=8.314 #gas constant, J/K mol\n", "deltaG0=5.4*10**3 #standard free energy, kJ/mol\n", "pNO2=0.122 #pressure of NO2, atm\n", "pN2O4=0.453 #pressure of N2O4, atm\n", "\n", "#Calculation\n", "import math\n", "deltaG=deltaG0+R*T*math.log(pNO2**2/pN2O4) #here solubility product is equal to equilibrium constant\n", "\n", "#Result\n", "if(deltaG<0):#equilibrium determination\n", " d=\"net reaction proceeds from left to right to reach equilibrium\" \n", "else:\n", " d=\"net reaction proceeds from right to left to reach equilibrium\" \n", "print\"The free energy for the given reaction is :\",round(deltaG*10**-3,2),\"kJ/mol and\",d\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The free energy for the given reaction is : -3.06 kJ/mol and net reaction proceeds from left to right to reach equilibrium\n" ] } ], "prompt_number": 27 } ], "metadata": {} } ] }