Question

One of the students in lab decided to use two fractionating columns (one on top of the other) instead of just one. How would this:_________.
a) affect the separation between hexane and heptane?
b) affect the yield of recovered pure hexane?
c) affect the yield of recovered pure heptane.
Explain your reasoning.

Answer 1

Answer:

See detailed explanation.

Explanation:

Hello there!

In this case, according to the given description, it turns out possible for us to infer that the second fractionating column on top of the first one will favor the light product, in this case hexane as it has the lowest boiling point and molar mass; in such a way, we can tell the following:

a) The separation between hexane and heptane will be increased as a purer hexane-rich product will be obtained on the top of the second column.

b) Will be increased as well, because the second column will remove more heptane.

c) Also, more pure heptane will be obtained on the bottom of the two columns, yet the most favored yield will be that of hexane.

All of the aforementioned is possible due to the fact that the second column will remove the amount of heptane that could not be removed on the top of the first column by taking the vapor-liquid equilibrium further from the first column's maximum separation, which is known as distillation sequences.

Regards!