The Story of Black Gold
🛢️ The Story of Black Gold
Deep beneath the North Sea, drilling rigs pump up a thick, smelly black liquid worth billions. This is crude oil — but in its raw form, it's useless. You can't put crude oil in your car or use it to make plastic bags.
The magic happens at oil refineries — huge industrial complexes where crude oil is separated into useful fractions. It's like taking a mixed bag of sweets and sorting them by size — except we're sorting molecules by their boiling points!
Fractional distillation is like sorting a mixed bag of sweets by size! Small sweets (short chains) float to the top, big sweets (long chains) sink to the bottom. In the fractionating column, small molecules rise to the top (low boiling point), big molecules collect at the bottom (high boiling point). Same principle, different scale!
Chemistry glossary
- What is crude oil?
- A mixture of many different hydrocarbons
- What is a hydrocarbon?
- A molecule made of hydrogen and carbon atoms ONLY
Crude oil is a mixture of hydrocarbons:
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🧠 Memory Aid: Size and Position
Remember the pattern in the fractionating column with this phrase:
Small molecules = low BP = rise to TOP | Big molecules = high BP = stay at BOTTOM
Think of hot air balloons — lighter, smaller balloons (molecules) rise to the top; heavier, larger ones stay at the bottom.
Properties going UP the column — remember the acronym FILMS:
- F — more Flammable
- I — fewer (weaker) forces between molecules
- L — Less viscous (runnier)
- M — smaller Molecule size
- S — lower boiling point (Smaller Bp)
Now try it yourself
Quiz · Question 1 of 20
A hydrocarbon is a compound that contains only:
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This topic in real past papers
Every real exam question we've found on crude oil, with a full worked answer.