A batch distillation column with three theoretical stages (the first stage is the still pot) is charged with 100 kmole of a 20 mole% n-hexane in n-octane mixture. At a constant reflux ratio R=1, if the still pot concentration is 6.4 mole%, how many moles of the charge must be distilled? The equilibrium data is: TEMPERATURE x, (n-hexane) y, (n-hexane) C mol/mol mol/mol 125.207 0 0 124.355 0.01 0.0434624 123.155 0.02 0.0846266 121.98 0.03 0.123639 120,83 0.04 0.160635 118.606 0.06 0.22907 116.478 0.08 0.290833 114.442 0.1 0.346705 109.726 0.15 0.464843 105.482 0.2 0.558581 101.643 0.25 0.633941 98.1493 0.3 0.695268 94.9527 0.35 0.745739 92.0131 0.4 0.787705 89.297 0.45 0.822927 86.7767 0.5 0.852742 84.4288 0.55 0.878175 82.2337 0.6 0.900024 80.1748 0.65 0.918916 78.2378 0.7 0.935347 76.4105 0.75 0.949714 74.6824 0.8 0.962339 73.0443 0.85 0.973483 71.4881 0.9 0.983361 70.8869 0.92 0.986999 70.2973 0.94 0.990473 69.7189 0.96 0.993792 69.4338 0.97 0.995396 69.1513 0.98 0.996965 68.8714 0.99 0.998499 68.3126 1 1