Answer 4.3.1: Why we always need to identify what we're solving for

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:

When we are asked to find the fractional conversion of the limiting reactant, which of the following words represent that?

1) the flowrate of HCl in steam 1/flowrate of HCl out in stream 2

2) the flowrate of HCl in steam 2/flowrate of HCl out in stream 1

3) the flowrate of propane in steam 2/flowrate of propane out in stream 1

4) the flowrate of propane in steam 1/flowrate of propane out in stream 2

5) the flowrate of propane in steam 1/flowrate of HCl out in stream 2

6) cannot tell from the information we have at this point

What is your answer?