Answer 4.3.1: Why we need extents of reaction equations

Problem:

The reaction between propane and hydrogen chloride to form propyl chloride and hydrogen is carried out in a continuous reactor. The product stream is analyzed and found to contain 27.45 mole% C3H7Cl, 27.45 mole % H2 and 14.6% HCl. The feed to the reactor contains only propane and hydrogen chloride. Calculate the fractional conversion of the limiting reactant and the percentage by which the other reactant is in excess. If the molar flow rate of the feed stream is 290 mol/s, what is the extent of reaction? (Give its numerical value and its units.)

Explanation:

Don't worry yet if you got this part wrong. You might have typed something in just a little bit wrong. The important thing is that you can start looking at the general equation with in - out...and be able to see where the terms are coming from in the table. We show you how you should have typed the answers in next:

overall equation: in - out + generation - consumption = 0
C3H8 balance: F1,C3H8-F2,C3H8-x=0
HCl balance: F1,HCl-F2,HCl-x=0
C3H7Cl balance: F1,C3H7Cl-F2,C3H7Cl+x=0
H2 balance: F1,H2-F2,H2+x=0

If we didn't have to type these in and could just write them on a sheet of paper, they'd look like this:

overall equation: in - out + generation - consumption = 0
C3H8 balance: F1,C3H8-F2,C3H8 - ξ = 0
HCl balance: F1,HCl - F2,HCl - ξ = 0
C3H7Cl balance: F1,C3H7Cl - F2,C3H7Cl + ξ = 0
H2 balance: F1,H2 - F2,H2 + ξ = 0

We're going to send you back to the main page to see which other steps may be important in this problem. But first, you'll need to write down the code number:

123

You may consider looking for other reaction example problems to work on to practice your extents of reaction equation writing when you are done with this problem...







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