One thousand kilograms per hour of a mixture of benzene (B) and toluene(T) that contains 50% benzene by mass are seperated 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.

Did you think we might write that as:

Ffeed,total?

Now we're going to have you help us figure out how to write down the other two pieces we can get from the problem statement. Which button below tells us that the flowrate of benzene in the top stream is 450 kg/hr?

Ffeed,benzene = 450 kg/hr
Ftop,toluene = 450 kg/hr
Fbottom,total = 450 kg/hr
Fbenzene,top = 450 kg/hr
Ffeed,feed = 450k g/hr
Ftop,benzene = 450 kg/hr
Ftop,benzene = 475 kg/hr
 

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