Simple iPython Notebook for calculations used in answering a Chem.SE question: http://chemistry.stackexchange.com/q/12256/3846

Fe_CuSO4.ipynb

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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "Standard boilerplate imports."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import numpy as np"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "Let's save the molar masses."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "MFe = 55.845 # g/mol\n",
      "MCu = 63.546"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 2
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "Now let's save the theoretical yield.\n",
      "\n",
      "The reactions are:\n",
      " - Fe + CuSO<sub>4</sub> <=> FeSO<sub>4</sub> + Cu\n",
      " - 2 Fe + 3CuSO<sub>4</sub> <=> Fe<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub> + 3 Cu"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "yld = np.asarray([1.00, 1.50]) # 100% and 150% for Fe2 and Fe3\n",
      "yld"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 3,
       "text": [
        "array([ 1. ,  1.5])"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "The masses of iron added and copper observed."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "mFe = 0.78 # g\n",
      "mCu_obs = 0.78 # g"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "Expected mass of copper for both reactions:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "mCu = mFe / MFe * yld * MCu\n",
      "mCu"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 5,
       "text": [
        "array([ 0.88756164,  1.33134247])"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "Error calculation:"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "err = np.abs(mCu_obs - mCu) / mCu\n",
      "err * 100 # now in %"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 6,
       "text": [
        "array([ 12.1187801 ,  41.41252006])"
       ]
      }
     ],
     "prompt_number": 6
    }
   ],
   "metadata": {}
  }
 ]
}