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Mangoes
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Homework Statement
A gas stream contains 18.0 mole % hexane and the remainder nitrogen. The stream flows to a condenser, where its temperature is reduced and some of the hexane is liquefied. The hexane mole fraction in the gas stream leaving the condenser is 0.05. Liquid hexane condensate is recovered at a rate of 1.50 L/min.
What is the flow rate of the gas stream leaving the condenser in mol/min?
The Attempt at a Solution
I looked up the specific gravity for hexane in the textbook this problem is assigned and found it to have a value of 0.659 at 20 degrees Celsius. Since hexane has a molecular weight of 86 g/mol,
1.5L hexane, by the specific gravity, is equal to 0.99 kg of hexane. By the molecular weight, this came out to be 11.47 moles of liquid hexane leaving the condenser.
I don't know where I'd go next with this though. Using conservation of mass, if I make up some initial amount of moles of hexane input into the condenser, I can subtract the liquid hexane output. The remaining would be the gaseous hexane output and then I'd use the mole fraction conversion to find the moles of gas, but the concentration of the output would be dependent on the initial input since there's a fixed liquid output only. A 100 mol input of hexane gives a different flow rate than a 1000 mol input.
I've been stumped on this question for a while now and I don't see where else I can go with this. Would anyone please guide me in the right direction?