{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 3: Thermodynamic and Chemical Equilibrium" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 1, Page no: 105" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "q = 120 # Heat from surrounding, cal\n", "W = 70 # Work done, cal\n", "\n", "# Solution\n", "delta_E = q - W\n", "\n", "print \"Change in internal Energy\", delta_E, \"cals.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Change in internal Energy 50 cals.\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 2, Page no: 105" ] }, { "cell_type": "code", "collapsed": false, "input": [ "print \"CH4 (g) + 2O2 (g) -> CO2 (g) + 2H20 (l)\"\n", "delta_n = 1 - (1 + 2)\n", "solution = - 2 * 2 * 298 # cals\n", "print \"Delta H - Delta E is:\", solution, \"cals\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "CH4 (g) + 2O2 (g) -> CO2 (g) + 2H20 (l)\n", "Delta H - Delta E is: -1192 cals\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 3, Page no: 105" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "delta_G = -16.0 # Kelvin cal\n", "delta_H = -10.0 # Kelvin cal\n", "T = 300 # Kelvin\n", "\n", "# Solution\n", "delta_S = (delta_H - delta_G) * 10 ** 3 / T # cal/deg\n", "new_T = 330 # Kelvin\n", "new_delta_G = (delta_H * 10 ** 3) - new_T * delta_S\n", "\n", "print \"The free energy at 330K is:\", \"{:.2e}\".format(new_delta_G), \"K cal\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The free energy at 330K is: -1.66e+04 K cal\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 4, Page no: 106" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "delta_S = -20.7 # cal /deg /mol\n", "delta_H = -67.37 # K cal\n", "T = 25 # deg C\n", "\n", "# Solution\n", "T += 273 # K\n", "delta_G = delta_H - (T * delta_S * 10 ** -3)\n", "print \"The change in free energy at 25deg C is:\", delta_G, \"K cal / mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The change in free energy at 25deg C is: -61.2014 K cal / mol\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 5, Page no: 106" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "wt = 1 # g\n", "delta_H = 149 # joules\n", "\n", "# Solution\n", "delta_H_fusion = delta_H * (10 * 12 + 8 * 1)\n", "print \"Enthalpy of fusion of naphthalene:\", delta_H_fusion * 10 ** -3, \"kJ/mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Enthalpy of fusion of naphthalene: 19.072 kJ/mol\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 6, Page no: 106" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "delta_H_acetylene = 230 # kJ/mol\n", "delta_H_benzene = 85 # kJ/mol\n", "T = 298 # K\n", "\n", "# Solution\n", "delta_H = delta_H_benzene - 3 * delta_H_acetylene\n", "print \"The enthalpy change for the reaction is:\", delta_H, \"kJ/mole\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The enthalpy change for the reaction is: -605 kJ/mole\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 7, Page no: 106" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Constant\n", "delta_H_vap = 2.0723 # kJ/g\n", "Tb = 373 # K\n", "\n", "# Solution\n", "delta_H_vap *= 18 # kJ/mol\n", "delta_S = delta_H_vap / Tb\n", "delta_G = delta_H_vap - Tb * delta_S\n", "delta_S *= 1000\n", "\n", "print \"The Entropy change is:\", \"{:.1f}\".format(delta_S), \"J/mol/K\"\n", "print \"The Free Energy change is:\", delta_G, \"kJ/mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Entropy change is: 100.0 J/mol/K\n", "The Free Energy change is: 0.0 kJ/mol\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 8, Page no: 106" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Constant\n", "R = 1.987 # cal /K /mol\n", "\n", "# Variables\n", "moles = 5\n", "Vo = 4 # litres, Initial Volume\n", "Vf = 40 # litres, Final Volume\n", "T = 27 # deg C\n", "\n", "# Solution\n", "print \"dS = nRln(V2 / V1)\"\n", "dS = moles * R * 2.303 * math.log10(Vf / Vo)\n", "print \"The change in entropy is:\", \"{:.2f}\".format(dS), \"cal / degree\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "dS = nRln(V2 / V1)\n", "The change in entropy is: 22.88 cal / degree\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 9, Page no: 107" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "wt = 10 # g\n", "heat_abs = 4.5 # K\n", "\n", "# Solution\n", "mole = 10 / 100.0 # mol\n", "delta_H = heat_abs / mole\n", "print \"The heat of the reaction is:\", delta_H, \"K cal / mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The heat of the reaction is: 45.0 K cal / mol\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 10, Page no: 107" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Constant\n", "R = 8.314 # J / K\n", "\n", "# Variables\n", "V_O2 = 2.8 # litres\n", "V_H2 = 19.6 # litres\n", "\n", "# Solution\n", "na = V_O2 / 22.4 # mol\n", "nb = V_H2 / 22.4 # mol\n", "Xa = na / (na + nb)\n", "Xb = nb / (na + nb)\n", "delta_S = (- R) * (na * math.log(Xa) + nb * math.log(Xb))\n", "\n", "print \"The increase in entropy on mixing is:\", \"{:.3f}\".format(delta_S), \"J / K\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The increase in entropy on mixing is: 3.132 J / K\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 11, Page no: 107" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Solution\n", "print \"For 1 mole of ideal gas,\"\n", "print \"\\tPV = RT or T = (PV) / R\\n\"\n", "print \"Differentiating with respect to V at constant P,\"\n", "print \"\\t[dT/dV]p = P/R\\n\"\n", "print \"Differentiating again with respect oto P at constant V\"\n", "print \"\\t[d2T/(dV*dP)] = 1/R\\n\"\n", "print \"Now differectiating with respect to P at constant V,\"\n", "print \"\\t[dT/dP]v = V/R\\n\"\n", "print \"Differentiating again with respect to V at constant P,\"\n", "print \"\\t[d2T/(dV*dP)] = 1/R\\n\"\n", "print \"From equations we get:\"\n", "print \"\\t[d2T/(dV*dP)] = [d2T/(dV*dP)]\\n\"\n", "print \"Hence, dT is a perfect differential.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "For 1 mole of ideal gas,\n", "\tPV = RT or T = (PV) / R\n", "\n", "Differentiating with respect to V at constant P,\n", "\t[dT/dV]p = P/R\n", "\n", "Differentiating again with respect oto P at constant V\n", "\t[d2T/(dV*dP)] = 1/R\n", "\n", "Now differectiating with respect to P at constant V,\n", "\t[dT/dP]v = V/R\n", "\n", "Differentiating again with respect to V at constant P,\n", "\t[d2T/(dV*dP)] = 1/R\n", "\n", "From equations we get:\n", "\t[d2T/(dV*dP)] = [d2T/(dV*dP)]\n", "\n", "Hence, dT is a perfect differential.\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 12, Page no: 108" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "delta_G_25 = - 85.77 # k J, Free Energy at 25 C\n", "delta_G_35 = - 83.68 # k J, Free Energy at 35 C\n", "Ti = 273 + 25 # K\n", "Tf = 273 + 35 # K\n", "\n", "# Solution\n", "print \"Equating the entropy change at both the temperatures.\"\n", "print \"(delta_H + delta_G_25) / Ti = (delta_H + delta_G_35) / Tf\"\n", "delta_H = - 148\n", "print \"The change in enthalpy for the process at 30C is\", delta_H, \"kJ\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Equating the entropy change at both the temperatures.\n", "(delta_H + delta_G_25) / Ti = (delta_H + delta_G_35) / Tf\n", "The change in enthalpy for the process at 30C is -148 kJ\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 13, Page no: 108" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Constants\n", "Lv = 101 # cal /g, Latent headt of vap.\n", "mwt = 78 # molecular weight of benzene\n", "\n", "# Variable\n", "moles = 2\n", "Tb = 80.2 # C, boiling point of benzene\n", "\n", "# Solution\n", "Tb += 273 # K\n", "delta_H = Lv * mwt\n", "delta_S = delta_H / Tb\n", "delta_G = delta_H - Tb * delta_S\n", "print \"delta_S =\", \"{:.2f}\".format(delta_S), \"cal / K\"\n", "print \"delta_G = delta_A =\", delta_G\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "delta_S = 22.30 cal / K\n", "delta_G = delta_A = 0.0\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 14, Page no: 109" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "V1 = 6 # dm^3\n", "V2 = 2 # dm^3\n", "T1 = 27 # C\n", "moles = 5\n", "\n", "# Solution\n", "print \"T1*V1 ^ (gamma - 1) = T2 * V2 ^ (gamma - 1)\"\n", "T1 += 273 # K\n", "T2 = T1 * (V1 / V2) ** (8.314 / 20.91)\n", "print \"The final temperature is\", \"{:.1f}\".format(T2), \"K\"\n", "q = 0 # Adiabatic process\n", "delta_E = - moles * 20.91 * (T2 - T1)\n", "delta_E /= 1000\n", "print \"q = \", q\n", "print \"Change is Energy is\", \"{:.2f}\".format(delta_E), \"kJ / mol\"\n", "W = - delta_E\n", "print \"W = \", \"{:.2f}\".format(delta_E), \"kJ / mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "T1*V1 ^ (gamma - 1) = T2 * V2 ^ (gamma - 1)\n", "The final temperature is 464.3 K\n", "q = 0\n", "Change is Energy is -17.18 kJ / mol\n", "W = -17.18 kJ / mol\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 15, Page no: 109" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Constant\n", "R = 8.314 # J / K mol\n", "\n", "# Variables\n", "mole = 1\n", "V1 = 5 # dm^3\n", "V2 = 10 # dm^3\n", "T = 300 # K\n", "\n", "# Solution\n", "print \"For isothermal and reversible process,\"\n", "delta_E = delta_H = 0\n", "delta_A = delta_G = - 2.303 * mole * R * T * math.log10(V2 / V1)\n", "q = W = - delta_G\n", "print \"delta_E = delta_H =\", delta_H\n", "print \"delta_G = delta_A =\", \"{:.3f}\".format(delta_G), \"J / mol\\n\"\n", "print \"For isothermal and reversible expansion\"\n", "print \"q = W = -delta_G =\", \"{:.3f}\".format(W), \"J / mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "For isothermal and reversible process,\n", "delta_E = delta_H = 0\n", "delta_G = delta_A = -1729.159 J / mol\n", "\n", "For isothermal and reversible expansion\n", "q = W = -delta_G = 1729.159 J / mol\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 16, Page no: 109" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Constant\n", "R = 8.314 # J / K mol\n", "\n", "# Variables\n", "n = 5 # moles\n", "T = 27 # C\n", "V1 = 50.0 # L, Initial Volume\n", "V2 = 1000 # L, Final Volume\n", "\n", "# Solution\n", "T += 273\n", "delta_G = 2.303 * n * R * T * math.log10(V1 / V2)\n", "delta_G /= 1000\n", "print \"The free energy change is\", \"{:.3f}\".format(delta_G), \"k J\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The free energy change is -37.367 k J\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 17, Page no: 110" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "delta_H_neu = - 51.46 # k J/mol, neutralization\n", "delta_H_ion = - 57.1 # k J/mol, ionization\n", "\n", "# Solution\n", "delta_H = - delta_H_ion + delta_H_neu\n", "print \"The head of ionization for NH4OH is\", delta_H, \"kJ / mol\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The head of ionization for NH4OH is 5.64 kJ / mol\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 18, Page no: 110" ] }, { "cell_type": "code", "collapsed": false, "input": [ "print \"For 1 mole of an ideal gas,\"\n", "print \"PV = RT or V = (RT)/P\"\n", "print \"(dV/ dP) = -(RT/P^2)\\t (at constant temperature)\"\n", "print \"(d^2V/ (dP*dT)) = -(R/ P^2)\"\n", "print \"(dV/ dT) = (R/ P)\\t (at constant pressure)\"\n", "print \"(d^2V/ (dT*dP)) = -(R/ P^2)\\n\"\n", "print \"(d^2V/ (dT*dP)) = (d^2V/ (dP*dT))\\t[From above equations]\"\n", "print \"Hence, dV is an exact differential.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "For 1 mole of an ideal gas,\n", "PV = RT or V = (RT)/P\n", "(dV/ dP) = -(RT/P^2)\t (at constant temperature)\n", "(d^2V/ (dP*dT)) = -(R/ P^2)\n", "(dV/ dT) = (R/ P)\t (at constant pressure)\n", "(d^2V/ (dT*dP)) = -(R/ P^2)\n", "\n", "(d^2V/ (dT*dP)) = (d^2V/ (dP*dT))\t[From above equations]\n", "Hence, dV is an exact differential.\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 19, Page no: 110" ] }, { "cell_type": "code", "collapsed": false, "input": [ "print \"Let P1, V1, T1 and P2, V2, T2 b the initial and final\",\n", "print \"state, respectively of the system\"\n", "print \"W rev = nRT[P1/ P2 - 1]\"\n", "print \"W irr = nRT[1 - P2/ P1]\"\n", "print \"W rev - W irr = [nRT/(P1P2)]*(P1 - P2)^2\"\n", "print \"Because RHS of the above equation is always positive,\"\n", "print \"W rev > W irr\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Let P1, V1, T1 and P2, V2, T2 b the initial and final state, respectively of the system\n", "W rev = nRT[P1/ P2 - 1]\n", "W irr = nRT[1 - P2/ P1]\n", "W rev - W irr = [nRT/(P1P2)]*(P1 - P2)^2\n", "Because RHS of the above equation is always positive,\n", "W rev > W irr\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 20, Page no: 111" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Solution\n", "Eq_HI = 1.56 / 2\n", "Eq_H2 = 0.22 / 2\n", "Eq_I2 = 0.22 / 2\n", "Kc = Eq_H2 * Eq_I2 / (Eq_HI ** 2)\n", "print \"The equilibrium constant for the dissociation reaction\",\n", "print \"{:.4f}\".format(Kc)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The equilibrium constant for the dissociation reaction 0.0199\n" ] } ], "prompt_number": 20 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 21, Page no: 111" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "Kc = 0.5 # / mole^2 litre^2\n", "T = 400 # K\n", "R = 0.082 # litre atm degree^-1 mole^-1\n", "\n", "# Solution\n", "Kp = Kc * (R * T) ** (-2)\n", "\n", "print \"The given equilibrium is\"\n", "print \"\\t\\tN2(g) + 3H2(g) <--> 2NH3(g)\"\n", "print \"Kp is\", \"{:.3e}\".format(Kp)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The given equilibrium is\n", "\t\tN2(g) + 3H2(g) <--> 2NH3(g)\n", "Kp is 4.648e-04\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 22, Page no: 111" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "solubility = 7.5 * 10 ** - 5 # mol L^-1\n", "\n", "# Solution\n", "Ksp = 4 * (solubility ** 3)\n", "print \"Solubility product of the salt is\", \"{:.4e}\".format(Ksp), \"mol^3 / L^-3\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Solubility product of the salt is 1.6875e-12 mol^3 / L^-3\n" ] } ], "prompt_number": 23 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 23, Page no: 111" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "Ti = 25 # C\n", "S = 0.00179 # g / L\n", "\n", "# Solution\n", "S /= 170 # mol / L\n", "Ksp = S ** 2\n", "print \"Solubility product at 25 C is\", \"{:.4e}\".format(Ksp), \"mol^2 / L^-2\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Solubility product at 25 C is 1.1087e-10 mol^2 / L^-2\n" ] } ], "prompt_number": 25 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 24, Page no: 111" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "Ksp = 8 * 10 ** - 5 # Solubility product PbBr2\n", "disso = 80 / 100 # % dissociation\n", "\n", "# Solution\n", "S = (Ksp / 4) ** (1 / 3.0) # Solubility is 100%\n", "S_80 = S * (80 / 100.0)\n", "S_per_g = S_80 * 367 - 1.621\n", "print \"Solubility in gm per litre is\", \"{:.3f}\".format(S_per_g), \"gm / litre\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Solubility in gm per litre is 6.349 gm / litre\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 25, Page no: 112" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "n_acid = 1 # mole\n", "n_alcohol = 1 # mole\n", "T = 25 # C\n", "x = 0.667 # mole\n", "\n", "# Solution\n", "print \"Kc = [CH3COOC2H][H2O] / ([CH3COOH][C2H2OH])\"\n", "Kc = 4\n", "print \"[CH3COOH] = (2 - x) / V\"\n", "print \"[C2H5OH] = (1 - x) / V\"\n", "print \"[CH3COOC2H5] = [H20] = x / V\"\n", "print \"3x^2 - 12x + 8 = 0\"\n", "print \"x =\", 2.366, \"or\", 0.634\n", "print \"0.634 mole of ester would be formed, because the other value,\",\n", "print \"x = 2.366, is not permissible.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Kc = [CH3COOC2H][H2O] / ([CH3COOH][C2H2OH])\n", "[CH3COOH] = (2 - x) / V\n", "[C2H5OH] = (1 - x) / V\n", "[CH3COOC2H5] = [H20] = x / V\n", "3x^2 - 12x + 8 = 0\n", "x = 2.366 or 0.634\n", "0.634 mole of ester would be formed, because the other value, x = 2.366, is not permissible.\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 26, Page no: 113" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Variables\n", "n_acid = 0.2 # mole\n", "n_salt = 0.10 # mole\n", "Ka = 1.8 * 10 ** -5\n", "\n", "# Solution\n", "pH = - math.log10(Ka) + math.log10(n_salt / n_acid)\n", "print \"The pH of acidic buffer is\", \"{:.3f}\".format(pH)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The pH of acidic buffer is 4.444\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 27, Page no: 113" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Variables\n", "n_salt = 0.02 # mole\n", "n_base = 0.2 # mole\n", "pKb = 4.7\n", "\n", "# Solution\n", "pOH = pKb + math.log10(n_salt / n_base)\n", "pH = 14 - pOH\n", "print \"pH of a buffer solution is\", pH\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "pH of a buffer solution is 10.3\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem: 28, Page no: 113" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Variables\n", "n_H2 = 8.07 # moles\n", "n_I2 = 9.08 # moles\n", "T = 448 # C\n", "n_eqHI2 = 13.38 # moles\n", "\n", "# Solution\n", "x = n_eqHI2 / 2 + 6.69\n", "Kc = n_eqHI2 ** 2 / (n_H2 * n_I2)\n", "\n", "print \"H2 + I2 <--> 2HI\"\n", "print \"1 0 0\"\n", "print \"1 - 2xx x x\"\n", "print \"x/(1 - 2x) = (1/Kc)^0.5\"\n", "print \"Dissociation constant of HI is 106.75 x 10^-3\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "H2 + I2 <--> 2HI\n", "1 0 0\n", "1 - 2xx x x\n", "x/(1 - 2x) = (1/Kc)^0.5\n", "Dissociation constant of HI is 106.75 x 10^-3\n" ] } ], "prompt_number": 9 } ], "metadata": {} } ] }