Why do different gases condense to liquids on different trays in the fractionating column?

Explanation

**Step-by-Step Solution:**

1. **Understanding Fractional Distillation**: Fractional distillation is a process used to separate a mixture of liquids based on their different boiling points. In this process, a mixture is heated, and the components with lower boiling points vaporize first.

2. **Heating the Liquid Petroleum**: When liquid petroleum is heated in the fractionating column, it begins to vaporize. This means that the various components of the petroleum, which are gases at high temperatures, start to rise through the column.

3. **Vapor Movement in the Column**: As the vapors move up the fractionating column, they encounter cooler temperatures at different heights. The temperature gradient in the column is crucial because it allows for the separation of gases based on their boiling points.

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