One Group That Changes Everything
🍺 One Group That Changes Everything
The -OH group is like fitting a master key to a plain lock. Without it, the molecule (the lock) does nothing — inert, unreactive, chemically boring. Add the -OH group (the key) and the lock opens: the molecule can now dissolve in water, burn cleanly, and react in ways the original alkane never could. One small addition unlocks an entirely new range of chemistry.
The -OH functional group is the game-changer. This tiny addition turns unreactive alkanes into compounds that can dissolve in water, burn cleanly as fuels, and participate in countless chemical reactions.
From ancient brewery fermentation to modern industrial production, alcohols have shaped human civilisation. They're renewable fuels, essential solvents, and the starting point for making countless other chemicals.
Chemistry glossary
- What are alcohols?
- Organic compounds containing the -OH hydroxyl functional group
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🧠 Memory Aid: OH = Alcohol, -anol Ending
Two simple rules to remember alcohols:
- Functional group = -OH (hydroxyl) — always at the end of the chain
- Naming = same prefix as alkane + "-anol" ending
First four (same prefixes as alkanes):
MEPB + anol: Meth-anol, Eth-anol, Prop-anol, But-anol
For fermentation vs hydration: Fermentation = renewable, slow, low purity. Hydration = fossil fuel, fast, high purity. Think: the traditional (old) way (fermentation) is slow; the industrial (modern) way (hydration) is fast.
Now try it yourself
Quiz · Question 1 of 22
What is the functional group present in all alcohols?
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This topic in real past papers
Every real exam question we've found on alcohols, with a full worked answer.