Hydrocarbons and Crude Oil
Think of crude oil as nature's ultimate chemistry set - it's a complex mixture of hydrocarbons (molecules containing only carbon and hydrogen) that literally powers modern life. These molecules come in chains and rings, and each type has its own special job.
Fractional distillation is how we separate crude oil into useful bits. Picture heating oil in a massive tower where different substances boil and condense at different temperatures - gases for heating rise to the top, petrol sits in the middle, and thick bitumen for roads stays at the bottom.
The alkanes are the main family here, following the pattern CnH2n+2. Methane (CH₄) is the simplest, then ethane (C₂H₆), propane (C₃H₈), and butane (C₄H₁₀). The longer the chain, the higher the boiling point and the thicker (more viscous) it becomes.
Quick Test Tip: Remember that shorter chains = more flammable = better fuels. That's why petrol (short chains) works brilliantly in car engines, whilst bitumen (long chains) is perfect for road surfaces.
