We are going to do another distillation example:
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.

Let's think back to our three ways of moving through a problem statement:

1) Filling information in directly from the statement

2) Using the definition of mass fraction and the total mass to find the mass of one of the components

3) Writing a mass balance to solve for an unknown

Before we go any farther, though, how many rows would we need in our table?

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