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  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 3: Importance of State Functions: Internal Energy and Enthalpy"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example Problem 3.2, Page Number 45"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from math import log`\n",
      "#Variable Declaration\n",
      "betaOH = 11.2e-4           #Thermal  exapnasion coefficient of ethanol, \u00b0C\n",
      "betagl = 2.00e-5           #Thermal  exapnasion coefficient of glass, \u00b0C\n",
      "kOH = 11.0e-5              #Isothermal compressibility of ethanol, /bar\n",
      "dT = 10.0                  #Increase in Temperature, \u00b0C\n",
      "\n",
      "#Calcualtions\n",
      "vfbyvi = (1+ betagl*dT)\n",
      "dP = betaOH*dT/kOH-(1./kOH)*log(vfbyvi)\n",
      "\n",
      "#Results\n",
      "print 'Pressure increase in capillary %4.1f bar'%dP"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Pressure increase in capillary 100.0\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example Problem 3.4, Page Number 49"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Variable Declaration\n",
      "cpsubysy = 1000           #Specific heat ration of surrounding and system\n",
      "Tpreci = 0.006             #Precision in Temperature measurement, \u00b0C\n",
      "\n",
      "#Calcualtions\n",
      "dtgas = -cpsubysy*(-Tpreci)\n",
      "\n",
      "#Results\n",
      "print 'Minimum detectable temperature change of gas +-%4.1f \u00b0C'%dtgas"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Minimum detectable temperature change of gas +- 6.0 \u00b0C\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example Problem 3.6, Page Number 50"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from sympy import *\n",
      "\n",
      "#Variable Declaration\n",
      "n = 1.0           #number of mole of N2, mol     \n",
      "Ti = 200.0        #Intial Temperature, K\n",
      "Pi = 5.00         #Initial pressure, bar\n",
      "Tf = 400.0        #Intial Temperature, K\n",
      "Pf = 20.0         #Initial pressure, bar\n",
      "a = 0.137         #van der Waals constant a, Pa.m3/(mol2)\n",
      "b = 3.87e-5       #van der Waals constant b, m3/(mol)\n",
      "A, B, C, D = 22.5, -1.187e-2,2.3968e-5, -1.0176e-8\n",
      "                  #Constants in Cvm equation J, K and mol\n",
      "vi = 3.28e-3      #initial volume, m3/mol\n",
      "vf = 7.88e-3      #Final volume, m3/mol\n",
      "\n",
      "#Calculations\n",
      "T = symbols('T')\n",
      "dUT = n**2*a*(1./vi-1./vf)\n",
      "dUV = integrate( A + B*T + C*T**2 + D*T**3, (T,Ti,Tf))\n",
      "\n",
      "#Results\n",
      "print 'dUT = %4.1f J: This is wrongly reported in book'%dUT\n",
      "print 'dUV = %4.1f J'%dUV"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "dUT = 24.4 J: This is wrongly reported in book\n",
        "dUV = 4174.1 J\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example Problem 3.7, Page Number 53"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from sympy import *\n",
      "\n",
      "#Variable Declaration\n",
      "m = 143.0         #Mass of graphite, g     \n",
      "Ti = 300.0        #Intial Temperature, K\n",
      "Tf = 600.0        #Intial Temperature, K\n",
      "A, B, C, D, E = -12.19,0.1126,-1.947e-4,1.919e-7,-7.8e-11\n",
      "                  #Constants in Cvm equation J, K and mol\n",
      "M = 12.01\n",
      "\n",
      "#Calculations\n",
      "\n",
      "T = symbols('T')\n",
      "dH = (m/M)*integrate( A + B*T + C*T**2 + D*T**3 + E*T**4, (T,Ti,Tf))\n",
      "expr = A + B*T + C*T**2 + D*T**3 + E*T**4\n",
      "cpm = expr.subs(T,300.)\n",
      "qp = (m/M)*cpm*(Tf-Ti)\n",
      "err = abs(dH-qp)/dH\n",
      "#Results\n",
      "print 'dH = %6.1f kJ'%(dH/1000)\n",
      "print 'qp = %6.1f kJ'%(qp/1000)\n",
      "print 'Error in calculations %4.1f'%(err*100)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "dH =   46.8 kJ\n",
        "qp =   30.8 kJ\n",
        "Error in calculations 34.3\n"
       ]
      }
     ],
     "prompt_number": 19
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example Problem 3.9, Page Number 56"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Variable Declaration\n",
      "m = 124.0         #Mass of liquid methanol, g\n",
      "Pi = 1.0          #Initial Pressure, bar\n",
      "Ti = 298.0        #Intial Temperature, K\n",
      "Pf = 2.5          #Final Pressure, bar\n",
      "Tf = 425.0        #Intial Temperature, K\n",
      "rho = 0.791       #Density, g/cc\n",
      "Cpm = 81.1        #Specifi heat, J/(K.mol)\n",
      "M = 32.04\n",
      "\n",
      "#Calculations\n",
      "n = m/M\n",
      "DH = n*Cpm*(Tf-Ti)+ m*(Pf-Pi)*1e-6/rho\n",
      "\n",
      "#Results\n",
      "print 'Enthalpy change for change in state of methanol is %4.1f kJ'%(DH/1000)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Enthalpy change for change in state of methanol is 39.9 kJ\n"
       ]
      }
     ],
     "prompt_number": 24
    }
   ],
   "metadata": {}
  }
 ]
}