{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 7 - Principles of chemical equilibrium" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E1 - Pg 147" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the reaction gibbs energy\n", "#Initialization of variables\n", "import math\n", "G=-31. #kJ/mol\n", "T=37+273. #K\n", "Cadp=1/1000. #mmol/L\n", "Cp=8/1000. #mmol/L\n", "Catp=8/1000. #mmol/L\n", "R=8.314 #J/K mol\n", "#calculations\n", "Q=Cadp*Cp/Catp\n", "deltaG=G+R*T*math.log(Q) /1000.\n", "#results\n", "print '%s %.1f %s' %(\"Reaction Gibbs energy =\",deltaG,\" kJ/mol\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Reaction Gibbs energy = -48.8 kJ/mol\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E2 - Pg 149" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the gibbs energy\n", "#Initialization of variables\n", "Hr=-285.83 #kJ/mol\n", "Sr=-163.34 #J/ K mol\n", "T=298.15 #K\n", "#calculations\n", "Gr=Hr-T*Sr/1000.\n", "#results\n", "print '%s %.2f %s' %('Gibbs energy =',Gr,'kJ/mol')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Gibbs energy = -237.13 kJ/mol\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E3 - Pg 153" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate the change in gibbs energy\n", "#Initialization of variables\n", "import math\n", "aADP=1 #mol/L\n", "aP=1 #mol/L\n", "aATP=1 #mol/L\n", "aH2O=1 #mol/L\n", "aH=math.pow(10,-7) #mol/L\n", "G=10 #kJ/mol\n", "T=298. #K\n", "R=8.314 #J/K mol\n", "#calculations\n", "Q=aADP*aP*aH/(aATP*aH2O)\n", "Gr=G+R*T*math.log(Q)/1000.\n", "#results\n", "print '%s %.1f %s' %('Change in nGibbs energy =',Gr,'kJ/mol')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Change in nGibbs energy = -29.9 kJ/mol\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E4 - Pg 155" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the equivalent fration\n", "#Initialization of variables\n", "Gr=1.7*1000 #J/mol\n", "T=298. #K\n", "R=8.314 #J/K mol\n", "K=0.5\n", "#calculations\n", "GbyRT=Gr/(R*T)\n", "feq=K/(K+1)\n", "#results\n", "print '%s %.2f' %(\"Equivalent fraction = \",feq)\n", "print '%s' %(\"For the second part, Gr=1.7 + 2.48 ln(f/1-f)\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Equivalent fraction = 0.33\n", "For the second part, Gr=1.7 + 2.48 ln(f/1-f)\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example E5 - Pg 157" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the pressure of N2,H2,NH3 gases\n", "#Initialization of variables\n", "import math\n", "import numpy\n", "species=(['N2', 'H2', 'NH3'])\n", "change=(['-x', '-3x', '2x'])\n", "E=(['1-x', '3-3x', '2x'])\n", "print '%s' %(\"Concentration table\")\n", "print '%s' %(\"species\")\n", "print '%s' %(\"change\")\n", "print(E)\n", "K=977.\n", "#Calculations\n", "g=math.sqrt(27*K/4.)\n", "vector=([g, -(2*g +1), g])\n", "sol=numpy.roots(vector)[1]\n", "\n", "PN2=1-sol\n", "PH2=3-3*sol\n", "PNH3=2*sol\n", "K=math.pow(PNH3,2)/(math.pow(PH2,3) *PN2)\n", "#results\n", "print '%s %.2f %s' %(\"Pressure of N2 gas = \",PN2,\"bar\")\n", "print '%s %.2f %s' %(\"\\n Pressure of H2 gas =\",PH2,\"bar\")\n", "print '%s %.2f %s' %(\"\\n Pressure of NH3 gas =\",PNH3,\"bar\")\n", "print '%s %.2e %s' %(\"\\n K final =\",K,\"> it is close to original value.\")" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Concentration table\n", "species\n", "change\n", "['1-x', '3-3x', '2x']\n", "Pressure of N2 gas = 0.10 bar\n", "\n", " Pressure of H2 gas = 0.31 bar\n", "\n", " Pressure of NH3 gas = 1.79 bar\n", "\n", " K final = 9.77e+02 > it is close to original value.\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example I2 - Pg 148" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the equilibrium constant\n", "#Initialization of variables\n", "import math\n", "Gr=-3.40 #kJ/mol\n", "R=8.314 #J/k mol\n", "T=298. #K\n", "#calculations\n", "lnK=Gr*1000./(R*T)\n", "K=math.exp(lnK)\n", "#results\n", "print '%s %.2f' %('Equilibrium constant K= ',K)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Equilibrium constant K= 0.25\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example I3 - Pg 149" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the decomposition temperature\n", "#Initialization of variables\n", "Hr=178. #kJ/mol\n", "Sr=161. #J/K mol\n", "#calculations\n", "T=Hr*1000 /Sr\n", "#results\n", "print '%s %.2e %s' %(\"Decompostion temperature =\",T,\"K\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Decompostion temperature = 1.11e+03 K\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example I4 - Pg 151" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the standard reaction gibbs energy\n", "#Initialization of variables\n", "GCO2=-394. #kJ/mol\n", "GCO=-137. #kJ/mol\n", "GO2=0\n", "#calculations\n", "deltaG=2*GCO2-2*GCO+GO2\n", "#results\n", "print '%s %d %s' %('Standard reaction gibbs energy =',deltaG,' kJ/mol')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Standard reaction gibbs energy = -514 kJ/mol\n" ] } ], "prompt_number": 9 } ], "metadata": {} } ] }