fractional distillation of crude oil

what is fractional distillation?

The process of separating crude oil into fractions based on their boiling points.

Why can crude oil be separated by fractional distillation?

Because it is a mixture of hydrocarbons with different boiling points.

Where does fractional distillation take place?

In a fractionating column.

What is the first step in fractional distillation?

Crude oil is heated until it vaporizes.

Why is crude oil heated during fractional distillation?

To turn it into a gas so that it can be separated by boiling point.

What happens to the vapors as they rise up the fractionating column?

They cool down and condense at different levels based on their boiling points.

What is the temperature gradient in a fractionating column?

It is hot at the bottom and cool at the top.

Where do long-chain hydrocarbons condense in the fractionating column?

: At the bottom, where it is hotter.

Where do short-chain hydrocarbons condense in the fractionating column?

At the top, where it is cooler.

What is a fraction?

A group of hydrocarbons with similar boiling points and properties.

Name the main fractions obtained from crude oil (from top to bottom of the column).

Gases, petrol, kerosene, diesel, heavy fuel oil, and bitumen.

What is kerosene used for?

As fuel for aircraft.

Which hydrocarbons are the most volatile?

Short-chain hydrocarbons like gases.

Which hydrocarbons are the most viscous?

Long-chain hydrocarbons like bitumen.

What is the relationship between chain length and boiling point?

The longer the chain, the higher the boiling point.

Why are short-chain hydrocarbons better fuels?

They are more flammable and burn more cleanly.

What property allows long-chain hydrocarbons to condense at the bottom of the column?

they have a higher boiling point

What happens to hydrocarbons that remain as gases at the top of the column?

They are collected and used as fuel for heating or cooking.

Why are fractions with shorter hydrocarbons in high demand?

They are used in fuels like petrol and are more useful for energy production.

How does fractional distillation contribute to the petrochemical industry?

It provides raw materials like alkenes for making plastics and other chemicals.

Why is fractional distillation important?

It makes crude oil useful by separating it into products with specific uses.

What fraction is often further processed using cracking?

Long-chain hydrocarbons to produce shorter, more useful ones like petrol and alkenes.