A quick introductory look at the alcohols
3 marks · NormalExplain why methanol and ethanol are both classified as alcohols, even though their formulas are different. Include reference to naming rules in your answer.
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Both have the –OH (hydroxyl) functional group attached to a hydrocarbon chain, making them alcohols. Their names both end in '-ol', following the alcohol naming convention.
Also accept: Each molecule contains an –OH group and their names use '-ol'.
Common mistakes: Focusing only on hydrocarbon chain length, not functional group.; Ignoring naming conventions.
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Marking points
M1 · 1 mark · States both have –OH/hydroxyl functional group.
M2 · 1 mark · Mentions functional group attached to a hydrocarbon chain.
A1 · 1 mark · Includes link to the '-ol' naming convention.
Worked solution
Methanol (CH3OH) and ethanol (CH3CH2OH) are both alcohols because both have a hydroxyl (–OH) group attached to a hydrocarbon chain.
In naming, the '-ol' suffix is used to show the presence of the alcohol group.
Their names both use the '-ol' suffix, showing they are alcohols by IUPAC rules.