in a fractionating column, what process is caused by cooling?

The process caused by cooling in a fractionating column is condensation.

What happens in the column

• As vapors rise up the fractionating column, the temperature gradually decreases , so the vapors meet cooler surfaces.

• On these cooler surfaces, the vapors change back into liquid; this change of state from gas to liquid is called condensation.

Why condensation matters here

• Repeated cycles of evaporation (from heating) and condensation (from cooling) along the column help separate liquids with different boiling points more efficiently.

• Each condensation step enriches the liquid in higher‑boiling components and the rising vapor in more volatile (lower‑boiling) components, improving the overall separation.

TL;DR: In a fractionating column, cooling causes condensation of vapors back into liquid on the cooler parts of the column.

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