Who this is for: Cambridge IGCSE Coordinated Science (0654) students who want alcohols — names, structures and key reactions — to become a reliable source of marks instead of a formula-matching exercise.
What query it owns: how to understand and revise alcohols in Cambridge IGCSE Coordinated Science.
Why this is safe: this page owns the alcohols revision-guide angle, while Tutopiya’s Alcohols subtopic page owns the learning resource and the free Alcohols quiz owns the practice.

Alcohols are organic compounds containing the hydroxyl functional group (–OH) attached to a carbon chain. Cambridge IGCSE Coordinated Science (0654) expects you to name simple alcohols, draw their structures, describe properties of ethanol, and link alcohols to the wider homologous series. This guide connects each idea to the question types examiners use every year.

Key takeaways

• Alcohols belong to a homologous series with general formula CₙH₂ₙ₊₁OH.
• The functional group is –OH (hydroxyl); it gives alcohols their characteristic properties.
• Methanol (CH₃OH), ethanol (C₂H₅OH) and propanol (C₃H₇OH) are the alcohols most commonly tested.
• Ethanol is produced by fermentation of sugars and by hydration of ethene.
• Ethanol burns in air to give carbon dioxide and water; it is used as a solvent and fuel.

What are alcohols in Cambridge IGCSE Coordinated Science?

Alcohols are covalent compounds in which one or more hydroxyl groups are bonded to a carbon skeleton. Like alkanes and alkenes, they form a homologous series: each member differs by a –CH₂– group, and they share similar chemical properties because of the –OH group. Ethanol is the alcohol you meet most often — in fermentation, fuels and everyday solvents.

You can read the full explanation, structural diagrams and notes on Tutopiya’s Alcohols subtopic page before you attempt questions.

The alcohol homologous series — names and structures

Alcohol	Formula	Structural idea
Methanol	CH₃OH	One carbon; –OH on end carbon
Ethanol	C₂H₅OH	Two carbons; –OH on end carbon
Propanol	C₃H₇OH	Three carbons; –OH on end carbon
Butanol	C₄H₉OH	Four carbons; –OH on end carbon

All members follow CₙH₂ₙ₊₁OH. The –OH group is the functional group — the part of the molecule responsible for its chemical behaviour.

Ethanol — production, properties and uses

Aspect	What to know	Exam link
Fermentation	Yeast converts glucose to ethanol and CO₂ (anaerobic)	“Describe how ethanol is made.”
Hydration of ethene	Ethene + steam → ethanol (catalyst, high temperature/pressure)	Links to Alkenes
Combustion	Burns in oxygen → CO₂ + H₂O + energy	”Write the word equation for ethanol combustion.”
Uses	Solvent, fuel (bioethanol), alcoholic drinks	”State two uses of ethanol.”

Alcohols in past-paper wording: command words that matter

Command word / phrase	What the question wants	Typical alcohol stem
Name / draw	Give correct name or structure	”Draw the structure of ethanol.”
State the functional group	Identify –OH	”Name the functional group in alcohols.”
Describe	Give a process step by step	”Describe how ethanol is produced by fermentation.”
Compare	Differences between compounds	”Compare ethanol with ethane.”

Worked exam-style stems (how to answer the wording)

1. “State the general formula for the alcohol homologous series.” CₙH₂ₙ₊₁OH. Mark-scheme reward: correct formula with subscripts.
2. “Draw the displayed formula of ethanol.” Two carbon atoms single-bonded; –OH on one end; remaining bonds to H. Reward: correct –OH group and two carbons.
3. “Describe how ethanol is produced by fermentation.” Yeast breaks down glucose in the absence of oxygen to produce ethanol and carbon dioxide. Reward: yeast, glucose, anaerobic, products named.

Test yourself with the Alcohols quiz once you can name alcohols and draw ethanol from memory.

How alcohols connect to the rest of Coordinated Science chemistry

Alcohols build on Homologous Series and Alkenes — ethene hydration makes ethanol. They lead into Polymers and broader organic chemistry. The Cambridge IGCSE Coordinated Science resource hub links every Organic Chemistry subtopic.

Common mistakes students make

• Writing the general formula as CₙH₂ₙ₊₂ (that is alkanes, not alcohols).
• Forgetting the –OH functional group when drawing structures.
• Confusing ethanol (C₂H₅OH) with ethane (C₂H₆).
• Stating fermentation needs oxygen (it is anaerobic).
• Missing that combustion products are always CO₂ and H₂O for complete combustion.

When you need more support

If alcohol questions keep costing marks, work through the Alcohols quiz, then get focused help from a Cambridge IGCSE Coordinated Science tutor.

Frequently asked questions

Is alcohols hard in Coordinated Science? The syllabus focuses on a small set of named alcohols and ethanol reactions — manageable once you learn the –OH group and general formula.

What is the functional group in alcohols? The hydroxyl group, –OH, bonded to a carbon atom in the chain.

How is ethanol made in industry? By hydrating ethene with steam (catalyst, high temperature and pressure) or by fermenting glucose with yeast.

How do I revise alcohols effectively? Draw methanol, ethanol and propanol from memory, state the general formula, then take the Alcohols quiz.

Ready to master Cambridge IGCSE Coordinated Science alcohols?

Start with the Alcohols subtopic page, then book a free trial with a Cambridge IGCSE Coordinated Science specialist to turn alcohol knowledge into guaranteed marks.

Ready to Excel in Your Studies?

Get personalised help from Tutopiya's expert tutors. Whether it's IGCSE, IB, A-Levels, or any other curriculum — we match you with the perfect tutor and your first session is free.

Book Your Free Trial