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Functional Groups: Quiz

Seven questions on identifying and naming functional groups, esters, isomers and boiling points, with explanations.

7 questionsIntermediate

7 questions

  1. Question 1EasyWhich family does CH₃CH₂OH belong to?
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    Answer: alcohol

    It contains an –OH group bonded to a carbon chain: ethanol, an alcohol.

  2. Question 2EasyWhat is the name of CH₃CH₂CHO?
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    Answer: propanal

    –CHO is an aldehyde group (ending -al). The chain has 3 carbons including the CHO carbon: propanal.

  3. Question 3MediumWhat is the ester formed from ethanol and methanoic acid?
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    Answer: ethyl methanoate

    The alcohol part comes first (ethanol → ethyl) and the acid part second (methanoic acid → methanoate).

  4. Question 4MediumWhich of these compounds has the highest boiling point?
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    Answer: ethanol, CH₃CH₂OH

    Only ethanol has an O–H bond, so only ethanol forms hydrogen bonds between its molecules (78 °C, against −24 °C for methoxymethane and −42 °C for propane).

  5. Question 5HardWhich pair are functional group isomers?
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    Answer: propanal and propanone

    Both are C₃H₆O with different functional groups (aldehyde and ketone). Ethanol and propan-1-ol differ by CH₂; the acid and the ester have different formulas; butane and 2-methylpropane are chain isomers in the same family.

  6. Question 6MediumWhat is the name of CH₃CH(OH)CH₂CH₃?
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    Answer: butan-2-ol

    The –OH is on carbon 2 when the chain is numbered from the nearer end (not 3).

  7. Question 7MediumWhich compound is a ketone?
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    Answer: CH₃COCH₂CH₃

    In CH₃COCH₂CH₃ (butanone) the C=O carbon has a carbon on each side. The others are an aldehyde, an ester and a carboxylic acid.