One thousand kilograms per hour of a mixture containing equal parts by mass of ethanol and water is distilled. Product streams leave the top and the bottom of the distillation column. The flowrate of the bottom stream is measured and found to be 673 kg/h, and the overhead stream is analyzed and found to contain 96 wt% ethanol. Find the flowrates of all components in all streams.

Streams\mass flow rate Total Ethanol Water
Feed 1000 Ffeed,ethanol Ffeed,water
Overhead Foverhead,total Foverhead,ethanol Foverhead,water
Bottoms 673 Fbottoms,ethanol Fbottoms,water



Which of the following mass balances can we write and solve (one equation with one unknown)?

Ffeed,total = Foverhead,total + Fbottoms,total
Ffeed,ethanol = Foverhead,ethanol + Fbottoms,ethanol
Ffeed,water = Foverhead,water + Fbottoms,water
Ffeed,total = Foverhead,water + Fbottoms,ethanol
Ffeed,total = Ffeed,water + Ffeed,ethanol

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