One thousand kilograms per hour of a mixture of benzene (B) and toluene(T) that contains 50% benzene by mass are separated by distillation into two fractions. The mass flow rate of benzene in the top stream is 450 kg B/h, and that  of toluene in the bottom stream is 475 kg T/h.  The operation is at steady state.  Write balances on benzene and toluene to calculate the unknown component flow rates in the output streams.

The problem statement isn't really as long as some of them that we are going to see later on. But there is quite a bit of information that we need to figure out how to use. The point of this example is to have you use what we just learned on the last page to write down information in a standard way.

From the problem statement, how do you think you would write down that the total feed flowrate was 1000 kg/hr? When you think you know the answer, click the button.

To return to more about how to keep track of information in a problem statement, click here.

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